JPS60166841A - Automatic analyzer of gas in oil - Google Patents

Abstract

PURPOSE:To enhance analytical accuracy by improving the separation of oil and the gas in the oil while performing stable gas analysis, by arranging a solenoid valve to a part above a gas extraction cylinder and arranging a selective check valve above said solenoid valve. CONSTITUTION:A point different from a conventional one resides in that the route of a solenoid valve 11 and a check valve 12 is connected to the piping to an analytical apparatus system extending upwardly from a gas extraction cylinder 1 and a selective check valve 14a is used in place of an oil detector 14 to be connected to said solenoid valve 15. In the selective check valve 14a, oil rising from below flows into a hollow body 27 and succeedingly rises while a float 29 is floated but, when the float 29 reaches a place where is the upper part of the hollow body 27 and has a narrow diameter, it is not raised thereabove and, therefore, the advance of oil is also inhibited. The float 29 is placed on a scale tray 28 in an oil absent state but, because the size of the float 29 is properly made smaller than that of the scale tray 28, extracted gas can pass the lateral side of the float 29.

Description

[Detailed description of the invention] [Technical field to which the invention pertains] The present invention relates to an automatic analyzer for gas dissolved in sample oil collected from an oil-immersed transformer, etc. [Prior art and its problems] Oil-immersed electricity When a thermal or electrical abnormality occurs inside a device such as a transformer, the surrounding insulating oil and insulation material decomposes and generates gas. These gases dissolve in the insulating oil and As the gas concentration increases, a well-known method is to extract and analyze the gas dissolved in oil (hereinafter referred to as gas in oil) and diagnose abnormal conditions inside the transformer from the analysis results. , it is widely used and effective both in Japan and abroad because abnormal conditions can be detected early.

Examples of methods for analyzing gas in oil include (1) extracting gas in oil using a Torricelli vacuum using mercury, and analyzing the extracted gas using a gas chromatograph.

(2) Gas in oil is extracted using a combination of a mercury diffusion pump and a Tegra pump, and the extracted gas is analyzed by gas chromatography.

etc., and are widely used.

However, while these methods are easy to implement, they also have the following problems.

(1) Since the operation is performed manually or semi-automatically, human labor is required throughout the entire process from start to finish.

(2) The operation is complicated, and the operator loses skill in order to perform highly accurate analysis.

(3) Since mercury is used, there is a risk of harm to the human body due to deterioration of the working environment due to mercury volatilization.

(4) The device is made of glass and is easily damaged.

In order to solve the above problems, an automatic analyzer for gas in oil invented by the present inventors was published in Japanese Patent Publication No. 52-209.
It is described in the magazine "Fuji Jiho" Vol. 45, No. 11, "Journal of Japan Petroleum Institute" Vol. 24, No. 2, etc.

Figure 1 shows the configuration of this automatic gas-in-oil analyzer and a system diagram for explaining the paths of oil and gas. il- Referring to FIG. 1, the sample oil collection process and the deaeration process will be explained separately.

1. Collection of sample oil into the bleed cylinder A piston 2 is disposed in the bleed cylinder 1 so as to be slidable in the axial direction by a piston rod 3 provided at the center. It is supported by a bearing 35 fixed by a member 34 at the bottom of 1, and has a negative passage through the part @ai-+. A bellows 4 is provided on the lower outer circumference of the piston 2 up to the bottom, and a first chamber 32 is formed between the bellows 4 and the bleed cylinder 1 . The piston 2 is provided with several small holes 6 that penetrate through the inside from the side surface thereof and reach the top surface. An O-ring 5 is disposed between a portion above the opening of the small hole 6 on the side surface of the piston 2 and the inner surface of the bleed cylinder 1.
A second chamber 33 is formed above.

On the other hand, a flow path for the sample oil flowing into and being discharged from the bleed cylinder 1 is connected to a container 8 containing the sample oil 7 collected from the oil-filled equipment.
A check valve 9 is connected from the container 8 to the bleed cylinder 1. It consists of a path that is piped so as to communicate with the first chamber 32 via the solenoid valve 10, and a path that connects the two paths of the extension via the solenoid valve 13.

Next, we will explain the procedure for collecting the sample oil 7 into the bleed cylinder 1 with the configuration up to this point.The piston 2 stops at the uppermost position in the bleed cylinder 1, and the solenoid valves 10, 11, and 13 are open. O), the check valve 9 allows oil to flow only from the side of the container 8,
Since oil flows through the check valve 12 only from the side of the bleed cylinder 1, when the piston 2 is lowered to the lowest position by the piston rod 3 in this state, the check valve 12 is opened between the bleed cylinder 1 and the piston 2. The sample oil 7 is
is a check valve9. It flows into the bleed cylinder 1 through the solenoid valves 13 and 11. At this time, the oil existing in the first chamber 32 is pressurized by the downward movement of the piston 2 and is forced out through the solenoid valve 10, but the oil is prevented from flowing toward the check valve 9 and is removed from the container 8. It joins with the incoming sample oil 7 and is collected into the second chamber 33 through the solenoid valve 13.11.

Next, when the piston rod 3 is operated to raise the piston 2 to its maximum position, some of the oil that had accumulated in the second chamber 33 flows into the first chamber 32 through the pore 6 of the piston 2. , most of them are solenoid valves 11. It passes through the check valve 12 and is discharged to the outside. At the same time, the first chamber 32 is depressurized and the sample oil 7 flows into it through the check valve 9 and the solenoid valve 10, but at this time the solenoid valve 13 remains open, so that the bleed cylinder 1
Some of the oil discharged from the upper part of the tank through the solenoid valve 11 gets mixed in. However, when raising the piston 2, the solenoid valve 1
3 may be closed.

When the above operation is repeated, for example, six times, the oil sampled in the bleed cylinder 1 is replaced with new sample oil 7. Finally, by stopping the piston 2 at the uppermost position, the oil accumulated in the second chamber 33 in the bleed cylinder 1 is discharged, and a certain amount of sample oil 7 is collected in the first chamber 32.

2. Deaeration of the sample oil An extraction gas path is provided outside the upper part of the extraction cylinder 1 and communicates with the extraction cylinder 1 in order to extract the gas in the sample oil 7 collected in the extraction cylinder 1 and guide it to the analyzer. is provided. That is, the extracted gas branches from the bleed cylinder 1, passes through the oil detector 14, passes through the solenoid valve 15, goes to the filter 16, and is further guided to the extracted gas sampling cylinder 17. Before and after this cylinder 17, solenoid valves 18 and 19 are installed, respectively. Prepare,
The extracted gas further flows into the extracted gas storage cylinder 20,
A gas flow path is provided so that the gas is guided through the electromagnetic valve 21 to a gas chromatograph (not shown).

Next, we will explain the procedure for sending the degassed gas from the sample collected in the extraction cylinder 1 to the gas chromatograph. When lowered, the upper second chamber 33 in the bleed cylinder 1 becomes depressurized, and the lower first chamber 33 becomes depressurized.
As the pressure in the chamber 32 increases, the sample oil collected in the first chamber 32 passes through the pore 6 in the upper part of the piston 2 and is violently injected into the second chamber 33 in the bleed cylinder 1. Since the area is in a vacuum state, the gas dissolved in the sample oil is separated from the oil. When the solenoid valve 15 is opened when the piston 2 reaches the lowest position and starts to rise again, the gas separated and extracted from the sample oil is guided through the filter 16 to the excess extracted gas sampling cylinder 17. is opened, the solenoid valve 19 is closed, and the extracted gas sampling cylinder 17 is kept in a reduced pressure state by lowering the piston 17a. When the solenoid valve 18 is closed and the solenoid valve 19 is opened to raise the piston 17a, the extracted gas collected in the collection cylinder 17 enters the extracted gas storage cylinder 20, which has been previously depressurized by lowering the piston 20a. By repeating these piston and valve operations about 20 times, the extracted gas sent to the extracted gas sampling cylinder 17 is finally collected in the extracted gas storage cylinder 20, and the gas dissolved in the sample oil 7 is collected. Since almost the entire amount is extracted, the extracted gas storage cylinder 20
The electromagnetic valve 21 connected to the gas is opened and the extracted gas is guided to a gas chromatograph (not shown) for gas analysis. It should be noted that the solenoid valve 22'f is branched between the solenoid valve 15 and the filter 16.
Since a gas flow path is provided and connected to an external argon gas source (not shown), this path is used to introduce argon gas under positive pressure after the analysis is completed, and the system is Oil and the like remaining in the piping can be discharged through the check valve 12.

However, during the above process, the injected sample oil returns to its original state through the pore 6, but not all of it returns, and some of it gradually rises through the solenoid valve 15, which remains open, and advances to the extraction gas sampling cylinder 17. Therefore, in the past, the bleed cylinder 1
The oil level is detected by the oil detector 14 installed above, and based on the signal, the solenoid valve 15 installed above the oil detector 14 is activated.
was closed to prevent oil from entering the extracted gas sampling cylinder 17.

However, subsequent research conducted by the present inventors revealed that even the provision of the oil detector as described above was still not sufficient, and that the present device had the following drawbacks.

1) When this apparatus is used for a long period of time, the oil remaining inside the piping gradually creeps and reaches the extracted gas sampling cylinder 17 and the gas flow path system of the analyzer, reducing the analytical performance of the apparatus.

2) A small amount of the extracted gas from the previous analysis remains between the oil detector 14 and the solenoid valve 15, so this will not be a problem if there is little gas in the oil analyzed last time, but if there is a lot of gas in the oil, the analysis will be delayed. Gives a negative effect to the value.

[Purpose of the invention]

An object of the present invention is to provide an automatic gas-in-oil analyzer that can completely separate sample oil and gas extracted from the sample oil and analyze gas-in-oil with high precision.

[Key points of the invention]

The present invention provides a solenoid valve near the upper part of the bleed cylinder and a selective check valve above the solenoid valve, thereby ensuring good separation of oil and gas in the oil and allowing stable gas analysis to be carried out. This is how it was done.

[Embodiments of the invention]

Figure 2 shows a system diagram of the main parts of the automatic gas-in-oil analyzer according to the present invention. Parts common to those in Figure 1 are given the same reference numerals, and the functions of each component are explained in principle. Since this is the same as in FIG. 1, the explanation will be omitted.

The difference between FIG. 2 and FIG. 1 is that the paths of the solenoid valve 11 and check valve 12 are not directly connected to the bleed cylinder 1, but are connected to piping extending upward from the bleed cylinder 1 to the analyzer system. In addition, a selective check valve 14a is used in place of the oil detector 14 in the piping to the analyzer system near the upper part of the bleed cylinder 1, and the mutual positional relationship with the solenoid valve 15 is set close to the bleed cylinder 1. The other is a solenoid valve 15, and a selective check valve 14a is connected to this solenoid valve 15.

Next, the conventional oil detector 14 and the selective check valve 14a used in the device of the present invention will be explained in detail.

FIG. 3 is a block diagram of the main parts of the oil detector 14, and FIGS. 4 and 5 are cross-sectional views of the main parts of the selective check valve.

In FIG. 3, a light emitting section 24 is placed on one side of the transparent tube 23 connected to the piping system. On the other hand, a light receiving section 25 that receives light emitted from the light emitting section 24 is arranged. Reference numeral 026 represents these power supply sections. When there is no oil in the transparent tube 23, the light emitting part 24
The light receiving section 25 that receives the light from the detector generates an electrical output, which opens the solenoid valve 15 connected to this detector as shown in FIG. 1 or FIG. 23, the light emitted from the light emitting section 24 is blocked by the oil and does not reach the light receiving section 25, and sufficient output is not generated. In this case, the solenoid valve 15 is closed and the The opening/closing operation of the electromagnetic valve 15 is automated depending on the presence or absence of oil in the transparent tube 23 in the oil detector 14, and the oil and extracted gas are passed through a hollow body 27 with a narrow diameter. A plate 28 is provided on which a spherical float 29 is placed.
Put it in. The oil rising from below flows into the hollow body 27 and continues to rise while keeping the float 29 afloat.
9 reaches the point where the diameter becomes narrower in the upper part of the hollow body 27, it does not rise any further, and therefore the oil is also stopped from advancing here. In the absence of oil, the float 29 rests on the perforated plate 28, but since the size of the float 29 is appropriately smaller than the perforated plate 28, the extracted gas cannot pass through the side of the float 29. can. Figure 5 shows a selection valve with a different shape from Figure 4.For example, the float 29 shown in Figure 5 is
It may also be shaped like a rocket. Note that the arrows in FIGS. 3 to 5 indicate the traveling direction of oil and bleed gas.

The mutual positional relationship between the oil stopper, which prevents oil from entering the analyzer and allows only the extracted gas to pass through, and the solenoid valve that is opened and closed by this stopper is the same as the conventional one shown in Figure 1. It is also conceivable to arrange the device in the opposite direction. That is, it is also effective to arrange the solenoid valve 15 closer to the bleed cylinder 1 and connect the oil detector 14 above it. In other words, even if the oil detector 14 is used, the connection with the solenoid valve 15 is
The operation of the piston 2 and the action of the solenoid valve 15 by the oil detector 14 are both the same as in FIG. 1, but the solenoid valve 15 is located in front of the oil detector 4. Even when the piston 2 reaches the upper limit position in the bleed cylinder 1, no pressure is applied to the oil detector 14, and accordingly, oil creep that enters the transparent tube 23 of the oil detector 14 does not proceed. , the separation of the sample oil and the extracted gas is improved, and since oil is present between the oil detector 14 and the solenoid valve 15 at the time of starting gas analysis, all the extracted gas is above the oil detector 14. Since all of the gas in the path is collected, the total amount of extracted gas to be analyzed is ensured.
There is an advantage that analysis accuracy can be improved.

However, in the present invention, taking into consideration the advantages of arranging the oil detector 14 and the solenoid valve 15 in reverse, the method of omitting the oil detector 14 and the solenoid valve 15 is further developed, and the selective check valve 14 is replaced in place of the oil detector 14.
a is used.

When the oil detector 14 shown in the configuration diagram in FIG. 3 is used, when air bubbles generated with rising oil reach the optical system part through the transparent tube 23, the light emitted from the light emitting part 24 is blocked by the air bubbles. Since the solenoid valve 15 is closed so that no output is generated in the light receiving section 25, the extracted gas is left in the bleed cylinder 1 at this time. Therefore, the entire amount of extracted gas cannot be collected unless the operation of the piston 2 of the extraction cylinder 1 is repeated at least 20 times. On the other hand, according to the present invention, instead of the oil detector 14, for example, as shown in FIG.
Since the selective check valve 14a as shown in FIG. 5 is used, many air bubbles in the rising oil are destroyed by the perforated plate 28, so that only the bleed gas passes through. Therefore, there is less bleed gas remaining in the bleed cylinder 1, and the piston 2 can be operated only about 10 times more than in the case of the oil detector 14, which is extremely efficient. In addition, since the oil detector shown in Fig. 3 uses light transmission, there is a concern that oil may stick to the inner wall of the transparent tube in the piping path and cause malfunction. There is no need to worry about such concerns at all with the selective check valves used for this purpose.Furthermore, selective check valves are more economical in that they require less equipment than oil detectors. However, this selective check valve itself cannot open or close the solenoid valve, so in FIG. 2, the solenoid valve 15 is closed only when the piston 2 reaches its maximum position. .

In addition to the above, in the conventional device shown in FIG. During the circulation process, the gas present in the bleed cylinder 1 is
In contrast, in the device of the present invention, the solenoid valve is removed as shown in Fig. 2. 1 and the check valve 12 are arranged higher than the uppermost position of the piston 2, all the gas present in the bleed cylinder 1 is exhausted during the oil circulation process, which may lead to errors in the analysis of the bleed gas. It disappears.

〔Effect of the invention〕

As explained above in the embodiments, in an apparatus for extracting and analyzing gas in oil such as insulating oil of a transformer, according to the present invention, a part of the circulation path of the oil from which sample oil is collected is connected to the piston of the extraction cylinder. By placing the solenoid valve necessary for the sample oil degassing process near the bleed cylinder and connecting the selective check valve above it, 〇(11) The outside air that gets mixed in when replacing the sample oil container does not accumulate in the upper part of the bleed cylinder, and is completely removed during the oil circulation process.

(2) Oil flowing into the selective check valve will not creep any further.

(3) Extracted gas is completely collected for analysis and an accurate amount is obtained (0) (4) The degassing process is carried out efficiently without any malfunctions. When performing analysis, the entire amount of gas dissolved in oil is collected in a short time and efficiently during the degassing process, reliably separated from the oil, and the oil reaches the analyzer system without contamination with outside air. This means that the analyzer is always kept in the best condition and gas analysis can be performed in a stable condition, which also has the great effect of improving analysis accuracy.

[Brief explanation of drawings]

FIG. 1 is a bold system diagram for explaining a conventional automatic gas-in-oil analyzer, FIG. 2 is a system diagram of main parts of the device of the present invention, FIG. Figure 5 is a cross-sectional view of a selective check valve.
2... Piston, 4... Bellows, 6
... Pore, 9.12 ... Check valve, 10
゜11, 13.15.18.19.21.22...
・・Solenoid valve, 14 ・・・・・Oil detector, 14a・
... selective check valve, 17 ... bleed gas sampling cylinder, 27 ... hollow body, 28 ...
- Perforated plate, 29...Float, 32...1st
Room, 33...Second Atsushi. Figure 1 Figure 2 ↑ Book 3 Figure 5 ↑ Figure 4

Claims (1)

[Scope of Claims] 1) A cylinder, a piston rod that passes through the cylinder, a piston that engages with the cylinder and follows the piston rod, and a piston that is arranged concentrically with the piston rod and that has one end connected to the piston. a first chamber formed between the daughter bellows and the cylinder; and a second chamber formed in the cylinder on the opposite side to the direction in which the piston rod penetrates. A second chamber is configured to communicate with the sample oil outlet, the oil outlet, and the extracted gas sampling section through valves, respectively, and between the external container and the cylinder. A path that communicates with the first chamber via a check valve and an electromagnetic damper, and a path that communicates with the second chamber located beyond the top dead center of the piston via an electromagnetic valve and a check valve. an oil circulation path connected to an oil discharge path, and a solenoid valve connected to the cylinder in order from the cylinder side in the vicinity of the cylinder in the path leading from the second chamber to the extracted gas sampling section; An automatic gas-in-oil analyzer characterized by comprising a valve. 2. In the device set forth in claim 1, the selective check valve has a perforated plate slightly smaller than the perforated plate provided on a perforated plate having a pore provided in a connecting pipe whose inner diameter is narrowed at both ends. 1. An automatic gas-in-oil analyzer, characterized in that it is equipped with a float having a diameter that is equal to the diameter of the float.