JPH0442775Y2 - - Google Patents

Description

[Detailed description of the invention] [Technical field to which the invention belongs] The present invention relates to an automatic analyzer for gas dissolved in sample oil collected from an oil-immersed transformer or the like.

[Prior art and its problems]

When a thermal or electrical abnormality occurs inside an oil-filled electrical device, such as a transformer, the insulating oil or insulating material around it decomposes and generates gas. These gases dissolve in the insulating oil and the gas concentration in the oil increases, so the gas dissolved in the oil (hereinafter referred to as gas in oil) is extracted and analyzed, and based on the analysis results, the inside of the transformer can be detected. A method for diagnosing abnormal conditions is already well known, and because abnormal conditions can be detected early, it is widely used and effective both in Japan and abroad.

Methods for analyzing gas in oil include, for example: (1) Extracting gas in oil using a Torrichieri 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 tetra pump, and the extracted gas is analyzed using a gas chromatograph.

etc., and are widely used.

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

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

(2) Operation is complicated, and operator skill is required 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, which was invented by the inventors of the present invention, was developed in 1973.
It is described in Publication No. 209, the magazine "Fuji Jiho" Vol. 45, No. 11, and the "Journal of Japan Petroleum Institute" Vol. 24, No. 2.

Figure 3 shows the configuration of this automatic gas-in-oil analyzer as well as a system diagram for explaining the paths of oil and gas. The process will be divided into the following steps: sample oil collection process, deaeration process, extraction gas mixing process, extraction gas injection process into the gas chromatograph, and system cleaning process.

1 Collection of Sample Oil into Extraction Cylinder A piston 2 is arranged in the extraction cylinder 1 so as to be slidable in the axial direction by a piston rod 3 provided at its center. A bellows 4 is provided on the lower part of the outer circumference of the piston 2 up to the bottom, and a first chamber 40 is formed between the bellows 4 and the extraction 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 of the side surface of the piston 2 above the opening of the pore 6 and the inner surface of the extraction cylinder 1, and a second A chamber 41 is formed.

On the other hand, the flow path of the sample oil flowing into the extraction cylinder 1 and being discharged is from the container 8 containing the sample oil 7 collected from the oil-immersed equipment via the electromagnetic valve 9, the check valve 13, and the electromagnetic valve 10. 1, a solenoid valve 11, a check valve 14, and a passage connected to the pipe extending upward from the extraction cylinder 1.
It consists of a path that is piped to the external free end of this system via the electromagnetic valve 12, and a pipe that connects these two paths.

Next, the procedure for collecting the sample oil 7 into the extraction cylinder 1 with the configuration up to this point will be explained. The piston 2 stops at the uppermost position in the extraction cylinder 1, the solenoid valves 9, 10, 11, and 12 are open, and the check valve 13 is closed because oil flows only from the side of the container 8. 14
Since oil flows only from the side of the extraction cylinder 1, when the piston 2 is lowered to the lowest position by the piston rod 3 in this state, the pressure in the second chamber 41 formed between the extraction cylinder 1 and the piston 2 is reduced. The sample oil 7 flows into the extraction cylinder 1 through the solenoid valve 9, the check valve 13 and the solenoid valve 11. At this time, the oil existing in the first chamber 40 is pressurized by the downward movement of the piston 2 and is forced out through the solenoid valve 10, but the flow is blocked toward the check valve 13 and the oil is removed from the container 8. Sample oil 7 flowing in
and is collected into the second chamber 41 through the solenoid valve 11.

Next, when the piston rod 3 is operated to raise the piston 2 to the upper limit position, a portion of the oil accumulated in the second chamber 41 flows into the first chamber 40 through the pore 6 of the piston 2. However, most of it is discharged to the outside through the solenoid valve 11, check valve 14, and solenoid valve 12. At the same time, the first chamber 40 is depressurized and the sample oil 7
The oil flows into this area through the electromagnetic valve 9, the check valve 13, and the electromagnetic valve 10, but at this time, some of the oil discharged from the pipe connecting the two paths is mixed in.

When the above operation is repeated, for example, six times, the oil sampled in the extraction cylinder 1 is replaced with new sample oil 7. Finally, by stopping the piston 2 at the upper limit position, the second chamber 41 in the extraction cylinder 1 is opened.
The oil accumulated in the chamber is drained and the sample oil 7 is placed in the first chamber 40.
A certain amount is collected.

2. Degassing the collected sample oil In order to extract the gas in the sample oil 7 collected in the extraction cylinder 1 and guide it to the analyzer, the extraction cylinder 1
An extraction cylinder path is provided outside the upper part of the extraction cylinder 1 so as to communicate with the extraction cylinder 1 . That is, the extracted gas is guided from the extraction cylinder 1 through the solenoid valve 16 and through the oil detector 17 to the extracted gas sampling cylinder 19. Solenoid valves 18 and 20 are provided before and after this cylinder 19, respectively, and the extracted gas is Furthermore, it flows into the injection cylinders 22, 26 and the extraction gas mixing cylinder 29. Hereinafter, the path from the gas injection cylinder 22 to the extraction gas mixing cylinder 29 will be collectively referred to as a metering valve system. The oil detector 17 is a beam switch consisting of a light emitting diode that emits light with a wavelength of 9400 mm and its receiver. A signal is output when the oil rises inside the glass tube and blocks the light. This signal closes the solenoid valve 16 to prevent oil from rising. Gas injection cylinder 2
Solenoid valves 21 and 24 are installed before and after 2, and solenoid valve 2 is installed at the top.
Similarly, a solenoid valve 25, 28 is provided before and after the gas injection cylinder 26, and a solenoid valve 27 is provided at the upper part, and the extracted gas is guided to the flow path in the gas chromatograph 42 through these solenoid valves 23 and 27. .
Note that detailed description of the configuration and operation of the gas chromatograph 42 will be omitted.

Next, the procedure for extracting dissolved gas from the sample collected in the extraction cylinder 1 will be explained. When the piston 2 at the highest limit position is lowered to the lowest position with the solenoid valves 9, 10, 11, 12, and 16 closed, the pressure in the upper second chamber 41 in the extraction cylinder 1 is reduced, and the lower pressure is reduced. As the pressure in the first chamber 40 increases, the sample oil collected in the first chamber 40 is violently injected into the second chamber 41 in the extraction cylinder 1 through the pore 6 in the upper part of the piston 2. At this time, since the area is in a vacuum state, the gas and oil dissolved in the sample oil 7 are separated. piston 2
When the solenoid valve 16 is opened when the oil reaches the lowest position and starts rising again, the gas separated and extracted from the sample oil 7 passes through the oil detector 17 and enters the extracted gas sampling cylinder 1.
9, but at this time, the solenoid valve 18 is
is opened and the solenoid valve 20 is closed, and the extracted gas sampling cylinder 19 is kept in a reduced pressure state by lowering the piston 19a. The extracted gas collected in the cylinder 19 is transferred to the piston 19a by closing the solenoid valve 18 and opening the solenoid valve 20.
When the pistons 22a, 2 are raised, the pistons 22a, 2
6a, 29a, solenoid valves 21, 24, 25,
28 and introduced into the reduced pressure metering valve system. By repeating these piston and valve operations approximately 30 times, the extracted gas collected in the extracted gas sampling cylinder 19 is finally collected within the metering valve system, and almost all of the gas dissolved in the sample oil 7 is extracted. be done.

3 Mixing of extracted gas in the metering valve system The gas extracted by the above operations has a different composition before and after the extraction operation, so the following operation is performed to make it uniform.

The solenoid valves 21, 24, 25, and 28 are opened, the solenoid valve 31 of the gas release path to the outside connected to the extraction gas mixing cylinder 29 is closed, and the piston 29a in the extraction gas mixing cylinder 29 is moved up and down. By performing this operation of driving the piston 29a up and down about six times, the extracted gas in the metering valve system is stirred and has a uniform composition. Finally the piston 29a
When stopping the drive, keep it at the maximum position.

4 Injecting the extracted gas into the gas chromatograph The uniformly mixed extracted gas is injected into the solenoid valves 21 and 2.
4, 25, 28 are closed, and the pistons 22a, 26a in the gas injection cylinders 22, 26 are raised with the electromagnetic valves 23, 27 open, thereby injecting the gas into the flow path of the gas chromatograph 42. This extraction gas is piped into the argon gas cylinder 50 and is caused by argon flowing into the gas chromatograph 4.
The sample is transported to a second column (not shown) and a detector for analysis.

5. Cleaning inside the metering valve system A part of the extracted gas collected in the metering valve system as described above is injected into the gas chromatograph 42 and analyzed. However, at this time, the injection cylinder 22,
The extracted gas collected in the metering valve system other than 26 remains in the piping and causes an error in the next analysis value. Cleaning is therefore required to remove residual extraction gas in this system.
This cleaning procedure is performed as follows. Extracted gas sampling cylinder 1 from extraction cylinder 1
Argon gas cylinder 5 connected to the path connecting 9
Solenoid valve 30 and solenoid valve 1 installed in the middle of piping from 0
8, 20, 21, 24, 25, 28, and 31, close the solenoid valve 16, and flow argon gas from the cylinder 50 into the metering valve system for 30 seconds to remove the remaining extraction gas from the system. Discharge. Next, when the solenoid valves 30 and 31 are closed and the piston 29a in the mixing cylinder 29 is moved up and down several times, the extracted gas remaining in each solenoid valve and the connection part is drawn out, so the solenoid valve 30 is closed again. , 31 are opened, argon gas is supplied from the cylinder 50 for 30 seconds, and the extracted gas is discharged to the outside of the system. This cleaning process is normally performed twice in one analysis process: during the collection of the sample oil 7 into the extraction cylinder 1 and during the analysis of the extracted gas.

The composition and operation of the automatic gas-in-oil analyzer have been outlined above.

As described above, in this device, in the process of guiding the gas in the sample oil from the extraction gas cylinder 1 to the sampling cylinder 19, the sample oil 7 injected into the second chamber 41 returns through the pores 6. At this time, all of the oil cannot return and some of it rises through the solenoid valve 16 which remains open, so this is detected using the oil detector 17 and the solenoid valve 16 is closed to remove the sample oil 7.
Care is taken to prevent the sample oil 7 from creeping further and to prevent the sample oil 7 from entering the extracted gas sampling cylinder 19.

However, it has been found that even if the oil detector 17 is used in this way, the separation of the sample oil 7 and the extracted gas is still insufficient in some cases. As mentioned above, the oil detector is a beam switch consisting of a light emitting diode and its light receiver, and is shown in partial perspective in FIG. 4. In Fig. 4, a beam switch light receiver 33 and a light receiver 34 are provided so as to sandwich the glass tube 32.The glass tube 32 in this part is made of a material that transmits light, and the oil sent from the extraction cylinder is filtered through the glass tube. A signal from the light receiver 34 generated when the oil rises in the tube 32 and blocks the light from the light receiver 33 closes the solenoid valve 16 (not shown in FIG. 4) to prevent the oil from rising any further. It is something to do.
FIG. 5 shows the cross-sectional shape of the glass tube 32.
However, if oil film-like bubbles are generated due to the properties of the oil, these bubbles cannot block the transmission of light, so they do not have the effect of closing the solenoid valve 16, and some of the oil escapes from the extracted gas sampling cylinder 19. It reaches the metering valve system and further the gas flow path system of the gas chromatograph 42, resulting in a decrease in analysis accuracy.

Therefore, in such an automatic gas-in-oil analyzer, it is desirable that the sample oil and extracted gas be reliably separated by the oil detector regardless of the properties of the oil.

[Purpose of invention]

The present invention was developed in view of the above points, and its purpose is to completely separate sample oil and gas extracted from sample oil, and to perform accurate and stable analysis of gas in oil. Our objective is to provide an automatic gas-in-oil analyzer.

[Key points of the idea]

This invention reliably prevents the rise of oil by providing a bubble rising obstacle to eliminate oil film-like bubbles in the transparent glass tube of the piping section where the oil detector is installed. This system improves separation and enables highly accurate and stable gas analysis in oil.

[Example of idea]

The present invention will be explained below based on embodiments.

The structure and operation of the automatic gas-in-oil analyzer to which the present invention is applied are the same as those already described, so a description thereof will be omitted. The present invention is based on a glass tube of piping where an oil detector is installed, and the cross-sectional shape of this glass tube is shown in FIG. FIG. 1 is a cross-sectional view of only the glass tube 32a of the present invention, and since the mounting conditions of the surrounding beam switches are the same as in FIG. 4, illustration is omitted. The difference between FIG. 1 and the conventional glass tube 32 shown in FIG. 5 is that the glass tube 32 in FIG. protrusions 32b
It is to have the following. In this way, when the oil film-like bubbles rise inside the pipe, the bubbles do not rise any further because there is a protrusion 32b that acts as an obstacle to eliminate the bubbles. This protrusion 3
2b may be heated and pressed from the outer periphery of the glass tube 32a so that the thick part partially protrudes from the inner surface of the glass tube 32a, or the protrusion 32b may be separately prepared and attached, but in any case. Even if the protrusion 32b
It is effective to form bubbles at different levels in the longitudinal direction of the glass tube 32a and to install an appropriate number of bubbles to cause the bubbles to collide and disappear. Also, when oil rises instead of oil film-like bubbles, the beam switch operates and the solenoid valve directly below the oil detector closes, just as in the case of a conventional straight pipe, so the oil flows inside the glass tube 32a and reaches the detector. It does not advance above the beam switch position.

As described above, the present invention provides an obstacle in the glass tube to prevent the bubbles from colliding and breaking before the bubbles reach the detector. Therefore, as long as it fulfills this role, it is not limited to a glass tube with a protrusion 32b on the inner surface as shown in FIG. It is also expedient to insert an insert 36 with a small hole 35 into the inner surface of a conventional straight glass tube 32. It is effective to use an insert 36 with a large number of small holes 35 connected in two stages as shown in FIG. 2, as this increases the probability of bubble collision. The shape of 36 and the number of connections may be determined depending on the actual situation.

In all of the above, oil film-like bubbles collide and break in the piping in the oil detector section, and obstacles are provided to prevent the bubbles from progressing, so the gas extracted from the sample oil is completely separated from the sample oil. It is something that can be analyzed.

[Effect of idea]

The automatic gas-in-oil analyzer described in Japanese Patent Publication No. 52-209, which was invented by the inventors of the present invention, has many advantages. The glass piping of the container was the simplest straight pipe, and was not necessarily sufficient in that the oil film-like bubbles could not block the light, but according to the present invention, as explained in the embodiment, Obstacles to prevent bubbles from advancing, such as protrusions on the inner surface or inserts with many small holes, are installed as appropriate on the inner surface of the glass tube, and the bubbles collide with these and disappear, thereby preventing the bubbles from flowing into the oil detector. The extracted sample oil does not rise any further, and only the gas extracted from the sample oil is completely separated here and sent to the gas chromatograph. As a result, highly accurate and stable gas-in-oil analysis is possible over a long period of time. It can be implemented without any maintenance.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the shape of the glass tube of the present invention, Figure 2 is a cross-sectional view of the inner tube inserted into the glass tube of the present invention, and Figure 3 is an automatic gas-in-oil analyzer to which the present invention is applied. FIG. 4 is a partial perspective view of a conventional oil detector, and FIG. 5 is a sectional view of a glass tube connected to the conventional oil detector. 32, 32a...Glass tube, 32b...Protrusion, 35...Small hole, 36...Insertion.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. An extraction cylinder that extracts dissolved gas from the sample oil after sampling the sample oil by operating a piston equipped with a bellows; an extraction cylinder that is piped to the extraction cylinder and temporarily stores the extracted gas; An extracted gas sampling cylinder that is injected by piston operation, a gas mixing cylinder that uniformly stirs the composition of the extracted gas sent from the extracted gas sampling cylinder by piston operation, and an extraction pipe that is piped between the extracted gas sampling cylinder and the mixed gas cylinder. In an automatic gas-in-oil analyzer equipped with an injection cylinder that injects gas into a gas chromatograph by piston operation, a transparent glass tube of an oil detector part connected in piping between the extraction cylinder and the extracted gas sampling cylinder. An automatic gas-in-oil analyzer characterized in that an obstacle is provided on the inner surface of the lower part to prevent passage of bubbles in the form of an oil film sent from the extraction cylinder. 2. The device according to claim 1 of the utility model registration claim, characterized in that the obstruction is formed by a plurality of protrusions that protrude at different levels perpendicularly to the longitudinal direction of the transparent glass tube of the oil detector section. Gas-in-oil automatic analyzer. 3. The device according to claim 1 of the utility model registration claim, characterized in that the obstruction is formed by an insert having a plurality of small holes in the longitudinal direction inserted into the transparent glass tube of the oil detector section. Gas-in-oil automatic analyzer.