JPH0476418B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a gas-in-liquid amount measuring device used for measuring the amount of dissolved gas in oil in oil-immersed equipment such as a transformer.

[Conventional technology]

In oil-filled transformers, when filling the transformer with insulating oil, the amount of dissolved air is generally It is degassed until it becomes less than 1%. In such work, it is necessary to check whether the amount of dissolved air has been removed sufficiently, and a gas-in-oil amount meter is used.

Previously, IEC Publication 567−1977 (Guide for
the Sampling of gases and of oil from oil−
filled electrical equipment and for the
A gas-in-oil measuring device was used as described in the analysis of free and dissolved gases. In particular, the trichury-type gas-in-oil measuring device is widely used as a simple measuring device.

FIG. 3 is a longitudinal cross-sectional view showing a conventional trichury-type gas-in-oil measuring device. In Figure 3, 11
12 is a gas discharge port, 12 is a two-way tank, 13 is a billet that collects gas in oil and measures the amount of gas,
14 is a three-sided pot, 15 is an oil extraction port, 16 is a gas extraction container, and 17 is mercury (Hg) in the gas oil extraction container 16.
18 is a mercury reservoir, and 19 is a flexible tube for communicating the gas extraction container 16 and the mercury reservoir 18.

A procedure for measuring the amount of gas in oil using a conventional gas amount measuring device composed of the above-mentioned parts will be described. In addition, the flow path of the three-way pot 14 is switched so that the brewet 13 side and the gas extraction container 16 side communicate with each other,
Next, open Kotoku 12. The mercury reservoir 18 is lifted above the height of the pot 12, the pot 17 is opened, the mercury level in the gas extraction container 16 is raised to the pot 12, the oil or air in the gas extraction container 16 is discharged, and the pot 12 is closed. After that, mercury reservoir 18
, lower the mercury surface on the gas extraction container 16 side to just below the three-way pot 14, and close the pot 17. After switching the flow path of the three-way pot 14 so that the oil sampling port 15 side and the gas extraction container 16 side communicate with each other, a container filled with sample oil or the like is connected to the oil sampling port 15. The mercury reservoir 18 is lowered, the pot 17 is opened, and the sample oil is introduced into the gas extraction container 16. After this, add more sample oil and air bubbles than the predetermined amount to the oil sampling port 15.
Then, one of the two ends of the flow path of the three-way drain 14 is between the oil extraction port 15 and the gas oil extraction container 16, and the other one is between the oil extraction port 13 and the gas extraction container 16. In other words, the three-way handle 14 is switched to the neutral position. Lift up the mercury reservoir 18, open the pot 17, and lower the mercury surface inside the gas oil outlet container 16.
Close. At this time, the space above the oil surface of the gas extraction container 16 becomes vacuum. When the gas extraction container 16 is held in hand and shaken vigorously, the feed oil is stirred by the mercury, and the gas dissolved in the oil is released into the space above the oil surface.
After shaking, open the pot 17 and remove the gas extraction container 16.
Lift up the mercury surface within. At this time, dissolved gas accumulates on the oil surface, which is guided to the shell 13 by switching the three-way tank 14. Repeat the above operation several times to collect the gas in oil in the oil tank 13, and finally, after draining the oil, align the mercury surfaces of the gas extraction container 16 side and the mercury reservoir 18 side, and collect the collected gas in oil. Read the amount on the scale of Billet 13.

[Problem that the invention seeks to solve]

In the conventional Trithier type gas-in-oil measuring device, the operation must be repeated several times in order to safely introduce the gas in oil into the burette, and measurement takes time. Extracted gas is calculated by guiding it through a thin tube such as a biuret, which is easily clogged with dirt and maintenance is troublesome, and it is difficult to measure when the amount of gas is small. Furthermore, it not only uses mercury, which is harmful to hygiene, and has problems such as the entire measuring instrument being made of glass, but also has a complicated structure and is very inconvenient to carry for field use.

This invention was made in order to eliminate the above-mentioned conventional drawbacks, and aims to provide a simple gas-in-oil gas amount measuring device that does not use mercury, is convenient to carry, and has high reliability. It is something.

[Means for solving problems]

Instead of using mercury to obtain a Trithierly vacuum, the present invention provides a vacuum-resistant container whose internal volume can be expanded, a passage opening/closing means for injecting a liquid to be measured into the vacuum-resistant container from the outside, and a method for dissolving dissolved gas from the liquid to be measured. a driving means for expanding the internal volume of the vacuum-resistant container in order to extract the liquid; It is equipped with a transparent plate that is brought into contact.

[Effect]

In this invention, by expanding the internal volume of the vacuum-resistant container, dissolved gas is extracted from the liquid to be measured injected inside, and a transparent plate having a scale and a recessed portion on the inner surface is used to absorb the extracted dissolved gas. Gas bubbles are brought into contact with each other, and the diameter of the bubbles can be quickly measured.

〔Example〕

An embodiment of the present invention will be described based on the drawings.
FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention, and FIG. 2 is an example of a conversion diagram for determining the amount of gas in oil from the bubble diameter. This conversion diagram varies depending on the amount of oil injected into the device of this invention and the expansion rate of the volume.
It shows the relationship in the case of double.

In FIG. 1, 1 is a vacuum-resistant container that accommodates the oil to be measured, 2 is a bellows attached to one end of the vacuum-resistant container 1 for the purpose of expanding the volume of the vacuum-resistant container 1, and 3 and 4 are the oil to be measured. Valve 5 serves as a flow path opening/closing means attached to two locations of the vacuum resistant container 1 for injecting or discharging the air into the vacuum resistant container 1. This is a bubble diameter reading plate made of a transparent material attached to the upper end of a true vacuum-proof container.The inner surface is formed in the shape of a concave lens, and the scale is 5.
A has been applied. 6 extends the bellows 2;
Handle for applying force for degeneration, 7
is a worm gear for allowing the handle 6 to rotate with a small force; 8 is a support column for fixing the vacuum-resistant container 1; 9 is a worm gear for extending and retracting the bellows 2. The handle 6, the worm gear 7, the support column 8, and the threaded rod 9 constitute a driving means.

A procedure for measuring the amount of gas in oil using the gas in oil amount measuring device configured as described above will be described. First, after opening the valves 3 and 4, the handle 6 is rotated to retract the bellows 2 to its minimum size. Next, invert the handle 6 upwards and the bubble diameter reading plate 5 downwards, inject the oil to be measured through the valve 3, allow it to sufficiently overflow from the valve 4, and confirm that there is no air inside the container. , close valve 3 and pipe 4. Thereafter, the bellows 2 is turned upside down to its original state, and the handle 6 is rotated to extend the bellows 2 to its maximum dimension. At this time, the vacuum-resistant container expands, a vacuum space is created above the oil to be measured, and dissolved air is released onto the oil surface. To speed up gas-liquid equilibrium, shake the measuring container by hand and let it stand for a while. Next, the handle 6 is rotated to retract the bellows 2 to its original position. At this time, the bubbles stay at the center of the upper reading plate 5 of the vacuum-resistant container 1, so after measuring the diameter of the bubbles with the bubble diameter reading plate, the bubble diameter is measured using the conversion chart shown in FIG. Determine the amount of gas in the oil from the diameter. Note that the gas amount conversion diagram in FIG. 2 is calibrated using a Toepler type extractor, which is said to have the highest extraction rate of gas in oil.

In this invention, the vacuum-resistant container 1 includes, for example,
Any suitable vacuum-resistant container can be used as long as it can obtain a vacuum or reduced pressure by expanding its internal volume, such as an expandable piston-type container.

In addition, although the above explanation was about measuring the amount of dissolved gas in oil, the gas amount measuring device in liquid of the present invention can also be used to measure the amount of dissolved gas in other liquids with low vapor pressure. Needless to say, it can be used.

〔Effect of the invention〕

As explained above, the present invention expands the internal volume of a vacuum-resistant container into which a liquid to be measured is injected, and has a concave portion on the inner surface provided with a scale, in which dissolved gas extracted from the liquid to be measured is used as bubbles. Since the bubble diameter is measured from a transparent plate, the measurement time can be shortened since the measurement can be performed in one operation instead of repeating the measurement operation several times as in the conventional example. Furthermore, since the transparent plate is provided with a scale, the bubble diameter can be quickly measured without using a scale or the like. Furthermore, since it has a simple structure that does not use glass thin tubes, it does not get clogged with dirt and the like, making maintenance easy and making it convenient for waiting and transporting. Furthermore, since there is no need to use mercury, it is possible to provide an instrument for measuring the amount of gas in liquid with excellent safety.

[Brief explanation of drawings]

Figures 1a and 1b show a gas-in-oil measuring device according to an embodiment of the present invention, a is a longitudinal sectional view thereof, and b is an A
- A plan view of the bubble diameter reading plate in the gas-in-oil measuring device as seen from line A. Figure 2 is a conversion diagram for determining the amount of gas in oil from the diameter of air bubbles in oil. Figure 3 is the conventional Trithierly method. FIG. 2 is a schematic diagram showing a gas-in-oil gas amount measuring device. 1... Vacuum resistant container, 2... Bellows, 3... Two-way valve, 4... Two-way valve, 5... Bubble diameter reading plate, 6... Handle, 7... Worm gear, 8
...Support column, 9...Threaded rod. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claims] 1. A vacuum-resistant container that reduces the internal pressure to a vacuum by expanding its internal volume, and a flow path provided in the vacuum-resistant container for injecting a liquid to be measured into the vacuum-resistant container from the outside. means, a driving means for expanding the internal volume of the vacuum resistant container in order to extract dissolved gas from the liquid to be measured poured into the vacuum resistant container, and a drive means provided on the vacuum resistant container and provided with a scale on the inner surface thereof. A gas-in-liquid gas amount measuring device comprising a transparent plate having a recessed portion and against which dissolved gas extracted from a liquid to be measured comes into contact as bubbles. 2. The in-liquid gas amount measuring device according to claim 1, characterized in that an expandable stainless steel metal bellows is used as the vacuum-resistant container. 3. The driving means is connected to the bellows container and the worm gear via a threaded concave and concave screw, and the rotation of the worm gear rotates one of the concave and convex screws, and the bellows expands and contracts accordingly. 3. The in-liquid gas amount measuring device according to claim 2, characterized in that: