JPH0495719A - Electrode for electromagnetic flowmeter - Google Patents

Abstract

PURPOSE:To obtain an electrode for an electromagnetic flowmeter by which the measurement of a flow rate that is stopped by the decrease in detecting capability of the electrode can be restarted quickly by setting one electrode part of both electrode parts in an electrode assembly in the electrode inserting hole of a measuring pipe, and using another electrode part as the standby electrode. CONSTITUTION:One conductive member (a) is taken out of an electrode inserting hole 5. Another conductive member (b) is set in the electrode inserting hole 5. The replacement of the conductive member (a) as the main electrode and the conductive member (b) as the standby electrode is immediately performed. Thus, the working time for replacing the electrodes can be shortened. One conductive member (b) of the two conductive members (a) and (b) is used as the standby electrode. The number of times for obtaining the electrodes can be reduced. The load for considering the special attention for the storing place of the standby electrode can be alleviated. Gasket attaching grooves 36 and 37 are provided at the different positions from the center of an attaching flange 32. The gasket attaching positions are changed and the sealing effect can be maintained when the sealing part is deformed by a cold flow.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electrode for an electromagnetic flowmeter that is attached to a measurement pipe through which a fluid to be measured flows.

[Conventional technology]

In general, a magnetic current indicator is widely known as an instrument that uses Faraday's electromagnetic induction phenomenon to extract an electromotive force proportional to the average flow rate of the fluid to be measured (conductive fluid) flowing in a pipe to measure the flow rate. There is.

Conventionally, this type of IT electromagnetic meter has been configured as shown in FIG. 7, for example. To explain this based on the same figure,
In the figure, the reference numeral 1 is a stainless steel measuring tube through which the fluid to be measured flows. It is housed in a case (not shown) for a magnetic current positioner, and two through holes 2 (only one shown) that open inwardly and outwardly are provided in the central part in the axial direction. A bottomed cylindrical electrode mounting boss 3 is integrally provided on the opening periphery of each of these prize passage holes 2 and protrudes from the opening periphery thereof.

Reference numeral 4 denotes a lining made of, for example, Teflon, which is continuously formed on the inner peripheral surface of the measuring tube 1, the inner peripheral surface and opening periphery of the through hole 2, and a part of the inner peripheral surface of the electrode attachment boss 3. . Two electrode insertion holes 5 (only one shown) having the same axis as the through hole 2 are formed in the lining 4. Moreover, on the opening periphery of these picture electrode insertion holes 5,
Two flat electrode mounting surfaces 6 (only one shown) are formed. Reference numeral 7 designates a pair of electrodes (only one of which is shown) that is partially exposed inside the tube, and is installed in the measurement tube 1 so that a portion of the electrode faces the electrode insertion hole 5, and is connected to each point in the fluid to be measured. It is configured to be able to detect the electromotive force generated in the electromotive force.

A flange 8 that faces the electrode mounting surface 6 is integrally provided on the outer peripheral surface of these picture electrodes 7, and this flange 8
An annular gas care groove 9 that opens toward the electrode mounting surface is formed on the end surface of the electrode. A gasket 10 made of Teflon is installed in the gasket groove 9 and interposed between the flange 8 and the electrode mounting surface 6. Reference numeral 1) denotes a cylindrical spring retainer with a bottom, which is screwed onto the inner peripheral surface of the opening of the electrode attachment boss 3, and has an insertion hole 12 in the center of the bottom surface through which the electrode 7 is inserted. Reference numeral 13 denotes a spring for attaching the electrode, which is elastically mounted between the spring retainer 1) and the end face of the flange 8. Also, 14
and 15 are the spring 13, the spring retainer 1), the end face of the flange 8, and the spring 1).
This is an insulating ring interposed between the two.

A pair of coils (not shown) are attached to the outer peripheral surface of the measuring tube 1 to form a magnetic field in a direction perpendicular to the flow direction of the fluid to be measured within the tube.

[Problem to be solved by the invention]

By the way, when the electrodes used in conventional electromagnetic flowmeters are used for a long period of time, they may corrode due to the fluid being measured, be scraped off by solid objects or fluids, or have solid objects attached to them. When the ability to detect electromotive force deteriorates, it becomes necessary to obtain new electrodes and replace the old and new electrodes. As a result, a large amount of work time is spent replacing the electrodes, and there is a problem in that the flow measurement that has been interrupted due to the decrease in the detection ability of the electrodes 7 cannot be resumed quickly.

The present invention has been made in view of these circumstances, and provides an electromagnetic flowmeter that can shorten the work time spent on replacing electrodes, and thereby quickly resume flow measurement that has been interrupted due to a decline in the detection ability of the electrodes. The present invention provides electrodes for use in

[Means to solve the problem]

The electromagnetic flowmeter electrode according to the present invention is an electrode assembly formed by combining two conductive members each having a T-shaped cross section and having an electrode portion protruding from the end face of a mounting flange. One of the three-dimensional electrode parts faces the electrode insertion hole of the measurement tube, and the other electrode part is used as a spare electrode.

[For production]

In the present invention, one conductive member is taken out from the electrode insertion hole, and the other conductive member is exposed to the electrode insertion hole. Components can be replaced instantly.

〔Example〕

EMBODIMENT OF THE INVENTION Hereinafter, the structure etc. of this invention will be explained in detail by the Example shown in the figure.

FIGS. 1(a) and 1(b) are a perspective view and a sectional view showing an embodiment of the electromagnetic flowmeter electrode according to the present invention, and in the following figures, the same members as in FIG. 7 are designated by the same reference numerals. Attached,
Detailed explanation will be omitted. In the figure, what is indicated by the reference numeral 31 is! An electrode assembly for a magnetic current positioner, including circular mounting flanges 32 and 33, and these flanges 32.
．． Two conductive members a and b, each having a T-shaped cross section and made of the same material and having electrode portions 34 and 35 protruding from each end surface of the measuring tube 33, are combined to have a cross-shaped cross section. It is configured to be able to detect the electromotive force generated at each point in the fluid to be measured within 1. This electrode assembly 3
Of both conductive members a and b of I, the electrode portion 34 of one conductive member a faces into the electrode insertion hole 5 and serves as a main electrode, and the electrode portion 35 of the other conductive member a serves as a spare electrode. It is configured as an electrode for. An electromotive force extraction portion 36 to which an external connection lead wire (not shown) is connected is provided on the tip end surface of this spare electrode (conductive member b). Also, the mounting flange 32.3 of the electrode assembly 31
3 is provided with annular gasket mounting grooves 37 and 38 that open at each end surface.

In the electromagnetic flow needle electrode configured in this way, by taking out one conductive member a from the electrode insertion hole 5 and allowing the other conductive member a to face inside the electrode insertion hole 5,
Conductive member a as a main electrode and at as a backup electrode
Since the sexual member can be replaced immediately, the work time spent on replacing the electrodes can be reduced.

Moreover, in this example, two conductive members a.

Being able to use one of the conductive members in b as a spare electrode reduces the number of times electrodes are obtained, which reduces the burden of paying special attention to the storage location of spare electrodes. .

Furthermore, in this embodiment, the gasket mounting groove 36.
37 are set at different positions from the center of the mounting flange 32, so that when the seal portion is deformed due to cold flow, the gas get mounting position can be changed to maintain the sealing effect.

In addition, in this embodiment, the sealing mechanism is set only on the end face of the mounting flange 32, 33, but the present invention is not limited to this, and the sealing mechanism can be mounted as shown in FIG. A sealing mechanism may be provided on the end faces of the flange 32 and 33, and O-ring mounting grooves 39 and 40 having different groove bottoms on the outer peripheral surface of the electrode portion 34 and 35 may be provided. As shown in FIG. 3, a seal @ bridge is set on the end face of the mounting flange 32, and a sealing mechanism is set by forming taber outer peripheral surfaces 41, 42 with different inclination angles on the electrode parts 34, 35. It doesn't matter in any way. Here, in the case shown in Fig. 2, the O-ring mounting groove in which the O-ring is attached when the seal part is deformed due to cold flow is changed from an O-ring mounting groove with a deep groove bottom to an O-ring mounting groove with a shallow groove bottom. By doing so, the reduced tightness of the O-ring can be restored to normal. Further, in the case shown in FIG. 3, the closeness of the sealing surface can be returned to normal by changing from the electrode portion 41 having a small inclination angle to the electrode portion 42 having a large inclination angle.

Moreover, in this example, both conductive members a.

It is possible to use the conductive member 36a and 36b as a spare electrode in b, but in this case, as shown in Fig. 4+8) and...), the setting positions of the electromotive force extraction parts 36a and 36b before replacement are fixed. By using the end face of the flange 32 or the tip face of the electrode part 34, the fluid contact surface and the flange sealing surface can be protected when used as a preliminary electrode, so damage to each part can be prevented. .

Furthermore, in this example, the conductive member a.

5. Although the case where the electrode lengths on both sides are the same is shown, the present invention is not limited to this, and as shown in FIG.
, b The electrode length of each example is t, l, t2 (L, > tz)
When the electrode part 34 of the aTLt member a faces the inside of the measurement tube 1 by setting the dimensions to .

Furthermore, in this embodiment, the case where the electrode assembly 3 is formed of a single IT member is shown, but in the present invention, as shown in FIG. 6 18) and (b), each electrode assembly is 2 T-shaped cross sections made of different materials
The electrode assembly 51, 52 may consist of two conductive members c, d. In this case, the presence of the preliminary electrode makes it possible to appropriately select a conductive member having durability against the fluid to be measured from both conductive members c and d.

In addition, the electrode assembly according to the present invention is attached to one meter of the measuring tube using, for example, a spring or a spring retainer.

〔Effect of the invention〕

As explained above, according to the present invention, there is provided an electrode assembly formed by combining two conductive members each having a T-shaped cross section and having an electrode portion protruding from the end face of a mounting flange. One of the three-dimensional two-type pole parts faced the electrode insertion hole of the measurement tube, and the other electrode part was used as a spare electrode, so take out one of the conductive members from the electrode insertion hole,
By bringing the other conductive member into the electrode insertion hole, the conductive member serving as the main electrode and the conductive member serving as the reserve electrode can be immediately exchanged. therefore,
Since the work time required for electrode replacement can be shortened, flow rate measurement that has been interrupted due to a decline in detection ability can be quickly resumed. Additionally, being able to use one of the two conductive members as a spare electrode reduces the number of times electrodes are obtained, which reduces the burden of paying special attention to where the electrodes are stored. It is also possible to simplify electrode management. Furthermore, since each electrode assembly is made of conductive members made of different materials, it is possible to appropriately select an electrode that has durability against the fluid to be measured among the picture electrodes.
This is extremely effective when the durability of each H/Pii member with respect to the fluid to be measured is unknown. Furthermore, since the electrode assembly is made up of electrically conductive members each having different external dimensions, even if the seal portion is deformed due to cold flow, the electrode portion can be changed to restore the seal surface to its normal state, and the electrode assembly can be made longer. Another advantage is that the sealing effect can be maintained over a period of time.

[Brief Description of the Drawings] Figures 1 (a) and ('b) relate to the present invention! A perspective view and a sectional view showing a magnetic current positioner electrode, FIGS. 2 and 3 are sectional views showing other embodiments, and FIG. 4 (al and ~) shows the connection state of the lead wire to the electromotive force extraction part. 31... Electrode assembly, 32.33... Mounting flange, 34.35... Electrode part, 36... Electromotive force extraction part, 37.38... Gas gent mounting groove, a. b. ...Conductive member.

Claims (4)

[Claims] (1) An electrode assembly formed by combining two conductive members each having a T-shaped cross section and having an electrode portion protruding from the end face of a mounting flange, one of which is a combination of two conductive members having a T-shaped cross section. An electrode for an electromagnetic flowmeter, characterized in that one electrode part faces an electrode insertion hole of a measuring tube, and the other electrode part is used as a spare electrode. (2) The electrode for an electromagnetic flowmeter according to claim 1, wherein each electrode assembly is made of conductive members made of the same material. (3) The electrode for an electromagnetic flowmeter according to claim 1, wherein each electrode assembly is made of conductive members made of different materials. (4) The electrode for an electromagnetic flowmeter according to claim 1, wherein each electrode assembly is made of conductive members having external dimensions different from each other.