JPH0124612Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is capable of detecting whether or not fuel gas is leaking, and the flow path for supplying gas to stoves, heating devices, and other gas consumption devices remains the same even during construction. The present invention relates to a device for maintaining pressure with gas.

When such equipment is supplying fuel gas to an apartment complex equipped with a large number of gas consumption devices, gas leakage may occur in the flow path that supplies the fuel gas to the gas consumption devices or in the gas consumption devices. This is necessary to detect whether or not the

Conventionally, when detecting a gas leak, the gas consuming device is not in use, the on-off valve provided upstream of the supply pipe that supplies fuel gas to the gas consuming device is closed, and this opening/closing valve is closed. A water column gauge is connected downstream of the supply pipe to detect changes in pressure downstream of the on-off valve. In such prior art, it is necessary to close the on-off valve after all gas consuming devices are put out of use. In order to detect gas leaks in an apartment complex all at once, a great deal of effort is spent coordinating and communicating inspection dates and times for each apartment. Furthermore, if the gas consumption device is accidentally put into use during a gas leakage inspection, fuel gas will be released from the gas consumption device after the opening/closing valve is opened, which is dangerous.

Additionally, in the past, during construction of a supply pipe that supplies fuel gas, air would enter the downstream side of the construction site, and therefore, after the construction was completed, fuel gas would be supplied to the downstream supply pipe. It was necessary to perform a gas purge and confirm that each gas consuming device was reliably combusted, which wasted a large amount of fuel gas and required a great deal of labor.

The purpose of this invention is to be able to easily detect leaks of fuel gas, and to perform gas purge operations downstream of the supply pipe even if the supply pipe supplying gas to gas consumption equipment is cut during construction. The objective is to provide a device that eliminates the need for

The present invention supplies the fuel gas to the gas consumption device 8 in the first
Fuel gas is supplied from the on-off valve 5 through a supply pipe 7, into which the fuel gas in the pressure vessel 11 is reduced in pressure by a pressure regulator 13,
3, 25 and the second on-off valve 26, the fuel gas in the pressure vessel 11 is the same as the fuel gas in the supply pipe 7, and the pressure of the fuel gas reduced by the pressure regulator 13 is: The pressure is selected to be lower than the pressure of the fuel gas in the supply pipe 7 and at which the combustion state of the pilot flame of the gas consumption device 8 can be maintained, and the pressure is selected to be lower than the pressure of the fuel gas in the supply pipe 7, and the pressure in the pipe between the pressure regulator 13 and the second on-off valve 26 is selected. 1
5, 19, 23, and 25, with the first on-off valve 5 closed and the second on-off valve 26 open, a flow rate and pressure lower than the flow rate and pressure at the time of ignition of the pilot flame of the gas consumption device 8 are applied. This is a device for detecting leakage of fuel gas and maintaining pressure, which is characterized in that a flow meter 17 and pressure gauges 21 and 22 are connected to each other for measurement.

FIG. 1 is an overall system diagram of an embodiment of the present invention. The housing complex 1 is further connected to a stove from a pipeline 3 buried in the ground 2 that supplies fuel gas such as city gas, via a supply pipe 4, a first on-off valve 5, a flow meter 6, and a supply pipe 7. Fuel gas is supplied to individual gas consuming devices 8 such as gas pumps and heating devices via on-off valves 9.

In order to detect gas leakage and maintain pressure downstream of the first on-off valve 5 in the housing complex 1, a device 10 according to the present invention is prepared. This device 10
Then, the gas from the pressure vessel 11 filled with the same gas as the fuel gas supplied from the pipe line 3 is transferred from the container valve 27 to the flexible pipe 12, the pressure regulator 13, and the on-off valve 1.
4, flexible tube 15, on-off valve 16, flow meter 17, on-off valve 18, pipeline 19, on-off valve 20, self-recording pressure gauge 2
1, water column gauge 22, flexible tube 23 and on-off valve 2
4 to the conduit 25. This conduit 25
is connected to the supply pipe 7 via the second on-off valve 26. The first on-off valve 5 is opened and the gas consumption device 8
The second on-off valve 26 remains closed while the fuel gas is being consumed. Pressure regulator 1
The primary pressure of No. 3 is measured by a Bourdon tube pressure gauge 28.

When detecting gas leakage in the housing complex 1 downstream of the first on-off valve 5, the gas consumption device 8
All of the on-off valves 9 individually provided are closed. Next, the container valve 27 and the on-off valves 14, 16, 1
Open 8, 20, 24, 26. The pressure regulator 13 is set to reduce the gas pressure in the pressure vessel 11 to a pressure that is 20 to 30 mmAq lower than the pressure of the fuel gas supplied from the pipe line 3. Therefore, the first on-off valve 5 is shut off. If a fuel gas leak occurs downstream of the first on-off valve 5 in the housing complex 1, the self-recording pressure gauge 21 and water column gauge 22 indicate that the pressure in the supply pipe 7 has increased before the first on-off valve 5 is closed. It decreases in comparison. Further, the flow meter 17 detects that gas from the pressure vessel 11 is flowing into the supply pipe 7 . In this way, it is detected that gas leakage has occurred in the housing complex 1. First on-off valve 5
When the pilot flame of the gas consumption device 8 remains lit before and after closing, the flow rate of fuel gas corresponding to the consumed flow rate of the pilot flame is detected by the flow meter 17, and the pressure gauge 21 and the water column are detected. Gauge 22 detects the drop in pressure.
That is, the pressure of the fuel gas reduced by the pressure regulator 13 is selected to be a pressure that can maintain the combustion state of the pilot flame of the consuming device 8, and the first on-off valve 5 is closed and the second on-off valve is closed. Even when the valve 26 is open, combustion of the pilot flame continues, ensuring safety. Generally, the fuel gas 3 is mixed with an odorant, and if a gas leak occurs at a relatively large flow rate, such as a pilot flame, there is no need to use the device 10, and the odorant is mixed in. A gas leak is identified by Therefore, the values detected by the flow meter 17, the self-recording pressure gauge 21, and the water column gauge 22 are even smaller than the values at the time of ignition of the pilot flame, and such small values are the values detected by the gas consumption device 8. It is confirmed that the value is not obtained by consumption of fuel gas, and thereby it is detected that gas is leaking.

When a certain on-off valve 9 is opened during detection of such gas leakage, fuel gas whose pressure has been reduced by the pressure regulator 13 is supplied from the pressure vessel 11 . Therefore, the gas consumption device 8 can be used, and its use can be continued even after the first on-off valve 5 is opened.

Supply pipe 4 between the pipe line 3 and the first on-off valve 5
Assume that construction work is being carried out at a location where the supply pipe 4 is to be cut. Prior to such construction, first, the on-off valve 9 that is continuously operated for each consumer device 8 is installed.
is closed, and then the first on-off valve 5 is closed. Therefore, the present device 10 is connected to the supply pipe 7, and the container valve 27 and the on-off valves 14, 16, 18, 20, 24, 26
open. In this way, inside the supply pipe 7, the fuel gas is
20 to 30 mmAq higher than the pressure before closing the on-off valve 5
The pressure remains at a low level. After completing the construction of the supply pipe 4, the supply pipe 4 may be filled with fuel gas by removing air mixed therein, and then the first on-off valve 5 may be opened. By closing the on-off valve 26, the present device 10 connected to the conduit 25 can be removed.

Most of the components of the device 10 shown in FIG. 1 are housed in a case 29 as shown in FIG. 2, which facilitates portability and improves workability.

By using the self-recording pressure gauge 21 and the water column gauge 22, gas leakage when the volume of the supply pipe 7 is small can be detected with high accuracy. If the flow meter 17 is used, regardless of the volume of the supply pipe 7,
Gas leakage flow rate can be detected.

As described above, according to the present invention, fuel gas is supplied to the gas consumption device 8 from the first on-off valve 5 via the supply pipe 7, and the fuel gas in the pressure vessel 11 is supplied to the pressure regulator 13 through the supply pipe 7. The pressure is reduced by the pipe 15,1
9, 23, 25 and the second on-off valve 26, the fuel gas in this pressure vessel 11 is the same as the fuel gas in the supply pipe 7, and the fuel gas is reduced in pressure by this pressure regulator 13. The pressure of the gas is selected to be lower than the pressure of the fuel gas in the supply pipe 7 and at a pressure that can maintain the combustion state of the pilot flame of the gas consumption device 8. The combustion state can be maintained when a gas leak is detected. Therefore, safety is maintained. When the pilot flame in a gas consumption device is in a combustion state, there is often no operator present near the gas consumption device 8, and it may not be possible to stop gas combustion in the gas consumption device 8. many. Even in such a case, the first on-off valve 5 is closed and the second on-off valve 5 is closed to detect fuel gas leakage.
When the on-off valve 26 is opened, the combustion state of the pilot flame is maintained, which prevents the pilot flame from being extinguished and fuel gas from being ejected from the pilot burner, thereby ensuring safety.

Moreover, in the present invention, the flow meter 17 and the pressure gauges 21, 22 measure the flow rate and pressure at the time of ignition of the pilot flame of the gas consumption device 8 with the first on-off valve 5 closed and the second on-off valve 26 open. Since it is possible to measure flow rates and pressures that are smaller than those of the pilot flame, it is possible to detect whether the pilot flame is in a combustion state or whether fuel gas is leaking at a flow rate lower than that during combustion of the pilot flame. . This is particularly advantageous for detection in apartment buildings, etc., since it eliminates the need for communication instructions to stop gas consumption.

Moreover, in the present invention, when gas work is carried out upstream of the first on-off valve 5, fuel gas whose pressure is reduced by the pressure regulator 13 from the pressure vessel 11 is guided to the supply pipe downstream of the first on-off valve 5. Therefore, in the present invention, there is no need to perform gas purge downstream of the first on-off valve 5 as in the prior art described above. This prevents a large amount of gas from being wasted and improves work efficiency.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an embodiment of the present invention, and FIG. 2 is a sectional view showing a part of the device 10 of the present invention. 1... Apartment house, 4, 7... Supply pipe, 5... First on-off valve, 6, 17... Flow meter, 8... Gas consumption device, 9, 14, 16, 18, 20, 24, 26
...Opening/closing valve, 11...Pressure vessel, 13...Pressure regulator, 21...Self-recording pressure gauge, 22...Water column gauge,
27...Container valve.

Claims (1)

[Claim for Utility Model Registration] Fuel gas is supplied to the gas consumption device 8 from the first on-off valve 5 through a supply pipe 7, and the fuel gas in the pressure vessel 11 is supplied to the pressure regulator 13 through the supply pipe 7. Therefore, the pressure is reduced, and the pipes 15, 19, 2
3, 25 and the second on-off valve 26, the fuel gas in the pressure vessel 11 is the same as the fuel gas in the supply pipe 7, and the pressure of the fuel gas reduced by the pressure regulator 13 is: The pressure is selected to be lower than the pressure of the fuel gas in the supply pipe 7 and at which the combustion state of the pilot flame of the gas consumption device 8 can be maintained, and the pressure is selected to be lower than the pressure of the fuel gas in the supply pipe 7, and the pressure in the pipe between the pressure regulator 13 and the second on-off valve 26 is selected. 1
5, 19, 23, and 25, with the first on-off valve 5 closed and the second on-off valve 26 open, a flow rate and pressure lower than the flow rate and pressure at the time of ignition of the pilot flame of the gas consumption device 8 are applied. A device for detecting leakage of fuel gas and maintaining pressure, characterized in that a flow meter 17 and pressure gauges 21 and 22 are connected to each other for measurement.