JPS588737B2 - gas extraction equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to analysis of dissolved gas in electrical insulating oil, which is necessary for early abnormality diagnosis of electric power equipment such as transformers and reactors that use electrical insulating oil. This invention relates to a gas extraction device used for analyzing the amount of dissolved gas in water supplied to water turbines, cooling equipment, etc.

For example, when describing the case of electrical insulating oil, generally,
Examples of gas extraction devices for dissolved gas in electrical insulating oil include a gas extraction device using a Torrichley vacuum, a gas extraction device using a combination of a mercury diffusion pump and a Teppler pump, and a gas extraction device using a vacuum pump and a moving valve.

However, the above-mentioned gas extraction device using a Toricherry vacuum creates a so-called Torichley vacuum using a glass leveling bottle containing mercury, and extracts the dissolved gas in electrical insulating oil into the vacuumed glass container. This method uses mercury and a glass container, so there are disadvantages such as the risk of mercury vapor escaping and the glass container being damaged.

In addition, a gas extraction device using a combination of a mercury diffusion pump and a Teppler pump, an oil rotary pump, a mercury diffusion pump, and a Teppler pump are used to maintain a vacuum state inside a glass degassing container, and electrically insulating oil is kept inside the degassing container. This method involves injecting mercury vapor to release dissolved gas and accumulate it in a gas storage container, but as with the aforementioned Torichley vacuum method, there is a risk of mercury vapor escaping and damage to the glass container.

Furthermore, a gas extraction device that uses a vacuum pump and a moving valve uses a vacuum pump to maintain the inside of the cylinder in a vacuum state, releases dissolved gas into the cylinder, and operates the moving valve when the degassing from the electrical insulating oil is completed. This method involves charging the extracted dissolved gas into a gas sample tube, but since the extraction operation can only be performed once on the same sample, it is difficult to sufficiently extract highly dissolved dissolved gas, and it is not possible to accurately extract dissolved gas. There are drawbacks such as difficulty in measuring the amount of dissolved gas.

In addition to these devices, there is also a dissolved gas extraction device that uses a carrier gas replacement method to extract the dissolved gas by replacing the dissolved gas in the electrical insulating oil with a carrier gas, but in this case, if the concentration of dissolved gas is low, the measurement is difficult,
There are drawbacks such as the fact that the amount of electrical insulating oil used as a sample is small, which tends to cause errors in measured values.

In view of these points, the present invention eliminates the need to use a glass device that is at risk of breakage, eliminates the risk of mercury vapor escaping, and eliminates the need for highly soluble dissolved gases. It is an object of the present invention to provide a gas extraction device capable of efficiently and sufficiently degassing.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In FIG. 1, reference numeral 1 denotes a degassing container for stirring electrical insulating oil as a sample with a stirring device 2 and separating its dissolved gas, and a switching valve 3 connected to the degassing container 1. A sample oil sampler 4 can be connected to the holder.

The degassing container 1 is connected via a valve 5 to a cylinder chamber 7a of a reciprocating piston device 7 driven by a drive motor 6 having a built-in linear reciprocating mechanism. A vacuum pump 10 is connected via a valve 8 and a three-way switching valve 9.

On the other hand, a plurality of branch pipes 12a and 12b (two in the figure) are connected to the pipe 11 connected to the three-way switching valve 9, and each branch pipe 12a and 12b is connected to the pipe 11 connected to the three-way switching valve 9, respectively. and connected to gas sample tubes 14a and 14b.

Thus, when the switching valves 13a and 13b are in the illustrated positions, the gas that has passed through the conduit 11 is supplied to the gas sample tubes 14a and 14b through the switching valves 13a and 13b, respectively, and
On the other hand, when the switching valves 13a, 13b are rotated by a predetermined angle and carrier gas is supplied from the carrier gas supply pipe 15 connected to the switching valves 13a, 13b, the carrier gas causes the gas in the sample tubes 14a, 14b to flow into the switching valves. 13a, 13b and further conduits 16a, 16b
Analyzers such as gas chromatographs (not shown)
It is arranged to be sent to

Further, the conduit 11 is provided with a pressure sensor 17, so that the amount of gas supplied to the gas sample tubes 14a, 14b through the conduit 11 can be measured.

Therefore, in order to extract dissolved gas in electrical insulating oil using the above device, first connect the sample oil sampler 4 to the switching valve 3, and then switch the switching valve 3 so that the sample oil sampler 4 communicates with the atmosphere. , while draining some of the electrical insulating oil from the sample, exclude air from the connection.

Next, the piston 7b of the reciprocating piston device 7 is actuated rightward in the figure by the drive motor 6 having a built-in linear reciprocating drive mechanism, thereby increasing the volume of the cylinder chamber 7a.

Therefore, the valves 5 and 8 are opened and the three-way switching valve 9 is operated to remove the cylinder chamber 1a and each gas sample tube 14a, 14.
b is connected to the vacuum pump 10, and the vacuum pump 10
By operating the cylinder chamber 7a, deaeration container 1,
Then, the insides of the gas sample tubes 14a, 14b, etc. are brought into a predetermined vacuum state.

When the inside of the cylinder chamber 7a etc. reaches a predetermined vacuum state in this way, the three-way switching valve 9 is switched to cut off the communication between the cylinder chamber 7a, gas sample tubes 14a, 14b, etc. and the vacuum pump 10, and the switching valve 3 is switched off. When opened, the electrical insulating oil in the sample oil sampler 4 flows into the degassing container 1, and the stirring device 2 is operated to stir the electrical insulating oil.

The dissolved gas in the electrical insulating oil is separated and released from the electrical insulating oil by the stirring, and the released dissolved gas is kept in the cylinder chamber 7a and the gas sample tube 1 which are kept in a vacuum state.
It flows into 4a and 14b and is accumulated.

Therefore, while the valve 5 is closed and the three-way switching valve 9 is maintained in a state where the cylinder chamber 7a and the gas sample tubes 14a, 14b communicate with each other, the drive motor 6 is operated to change the piston γb of the reciprocating piston device 7. move it to the left.

Therefore, the movement of the piston 7b forces the dissolved gas in the cylinder chamber Ta into the gas sample tubes 14a, 14.
It is transferred and charged to b.

When the gas sample tubes 14a, 14b are completely charged as described above, the valve 8 is closed and the piston 7b of the reciprocating piston device 7 is moved to the right again.

As a result, the inside of the cylinder chamber 7a is brought to a high degree of vacuum again, so that when the valve 5 is opened, the dissolved gas in the electrical insulating oil in the degassing container 1 is released from the electrical insulating oil and accumulated in the cylinder chamber Ia. The accumulated dissolved gas is sequentially transferred and charged into the gas sample tubes 14a and 14b by repeating the above-described operations.

In this way, by repeatedly performing the degassing and extraction operation for dissolved gases on the same sample of electrical insulating oil, even dissolved gases that have high solubility and are difficult to degas can be efficiently extracted.

The extracted dissolved gas is measured by a pre-calibrated pressure sensor 17, while the gas sample tube 14
The dissolved gas charged into the switching valves 13a, 14b
3b respectively to supply the carrier gas from the carrier gas supply pipe 15 to the gas sample pipes 14a, 14b, the conduits 16a, 16a, 16b via the switching valves 13a, 13b
16b, and is sent to an analytical device such as a gas chromatograph as appropriate.

FIG. 2 shows a further embodiment of the invention, in which a reciprocating piston device 20 is further connected to the branch conduit 12a.

That is, the branch conduit 12a communicates with the cylinder chamber 20a of the second reciprocating piston device 20.

Therefore, when extracting dissolved gas from electrical insulating oil, the piston 20b of the reciprocating piston device 20 is also moved to the right, and the cylinder chamber 20a is also brought into a vacuum state by the vacuum pump 10 along with the reciprocating piston device 7, etc. After reciprocating the piston 7b several times in the same manner as in the first embodiment, the piston 20b can be moved to the left to completely transfer the dissolved gas into the gas sample tubes 14a and 14b. can.

By the way, although the amount of dissolved gas generally differs depending on the electrical insulating oil of the sample, when the amount of dissolved gas is, for example, n times a certain reference amount, the internal volume of the cylinder 20a of the reciprocating piston device 20 is adjusted by the three-way switching valve 9. From gas sample tube 1
4a, 14b and the gas sample tube 14
By adjusting the volume to be (nt) times the sum of the volumes of a and 14b, the degree of vacuum in the degassing container can be kept almost constant regardless of the amount of dissolved gas, and under certain conditions. Gas can be extracted from electrical insulating oil.In addition, the present invention extracts and analyzes dissolved gas in water from water supplied to a water turbine or water supplied to cooling equipment, etc. using the same method as described above. It is also possible to perform gas extraction from various liquids.

Since the present invention is configured as described above, dissolved gas can be repeatedly extracted from a liquid by reciprocating the piston of the reciprocating piston device, and even dissolved gases with high solubility can be sufficiently extracted. The entire device is extremely small and lightweight, and since mercury is not used to extract dissolved gas, there is no risk of mercury vapor escaping, significantly improving the safety of analytical work. play.

[Brief explanation of the drawing]

FIG. 1 is a schematic system diagram of a gas extraction device of the present invention, and FIG. 2 is a schematic system diagram showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Deaeration container, 2... Stirring device, 4... Sample oil sampler, 5, 8... Valve, 7... Reciprocating piston device, 9... Three-way switching valve, 10 ...Vacuum pump, 14a
, 14b... gas sample tube, 20... reciprocating piston device.

Claims (1)

[Scope of Claims] 1. A gas extraction device used for analysis of dissolved gas in a liquid, etc., which includes a degassing container for separating dissolved gas from a liquid that is a sample, and extracting the dissolved gas from the degassing container. A reciprocating piston device driven by an external drive mechanism that discharges the gas into the gas sample tube, and a reciprocating piston device that is connected to the degassing container, the cylinder chamber of the reciprocating piston device, and the gas sample tube via a switching valve, A gas extraction device characterized by comprising a vacuum pump that brings the inside of the deaeration container, cylinder chamber, etc. to a predetermined vacuum state before starting the extraction operation. 2. In a gas extraction device used for analysis of dissolved gas in liquid, etc., there is a degassing container for separating dissolved gas from the liquid sample, and a gas sample tube that extracts the dissolved gas from the degassing container. A reciprocating piston device is connected to the degassing container, the cylinder chamber of the reciprocating piston device, and the gas sample tube via a switching valve, and the degassing container, cylinder chamber, etc. 1. A gas extraction device comprising: a vacuum pump for creating a predetermined vacuum state; and a second reciprocating piston device connected to the inlet side of the gas sample tube.