JPH09178035A - Ball valve for gas conduit tube with built-in flow meter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily execute a maintenance and inspection work of a flow meter built in a valve body from the outside on the ground, in a ball valve in which interception and flow measurement of gas can be simultaneously performed. SOLUTION: This ball valve is provided with a flow detecting body 34 suspended in the through hole 25 of a valve body 22, a flow measuring means (a signal conversion part 37, and a flow computer 42) computing a gas flow based on a signal obtained from the flow detecting body 34, and the valve body 22 and the valve main body 20 are provided with a hollow passage 33 communicating to the through hole 25 of the valve body and for lifting the flow detecting body 34 over a valve main body 20, and a hollow chamber 36 for maintenance and inspection communicating to the hollow passage 33 on the upper part of the valve main body 20. This valve is constituted so that at closing the valve, the flow detecting body 34 is lifted into the hollow chamber 36 through the passage 33 under the condition in which communication of gas between the upper stream side and the lower stream side of the valve body 22 is insured, and the hollow chamber 36 is opened from the outside on the ground so as to make possible maintenance and inspection of the flow detecting body 34.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ball valve used for shutting off a gas on a path of a gas supply conduit, and more specifically, a flow meter is built in the valve body and the flow meter is maintained from outside the ground. The present invention relates to a ball valve configured to allow inspection work.

[0002]

2. Description of the Related Art As shown in FIG. 1, a gas supply system is
The gas (pressure = 10 kg / cm ² or more) produced in the factory 1 is sent to the governor station 3 through the high pressure conduit 2,
Gas decompressed at governor station 3 (pressure = 10k
(less than g / cm ^{2 to 1} kg / cm ² or more) is delivered to the district governor 5 in each consumption area by the medium pressure conduit 4, and the district governor 5
A method is adopted in which the gas (less than 1 kg / cm ² ) depressurized in 1 is supplied to each consumer 7 through the low pressure conduit 6.

In order to prevent gas supply to this gas supply system based on a command from the central monitoring center 8 as a measure against a disaster such as an earthquake, the gas supplied from the factory 1 is urgently supplied to the high pressure conduit 2 so that the gas supply can be interrupted. A shutoff valve 10 is provided, and a regional block valve 11 (shutoff valve) is provided in the medium-pressure conduit 4 leading to the district governor 5 in each consumption area.

At the installation position of the regional block valve 11, it is possible to simultaneously measure the flow rate of the gas at the same time as shutting off the gas so that it can be controlled whether or not the supply gas is stably supplied to each of the downstream consumption areas. I have to. For this reason,
At the installation position of the regional block valve 11, as shown in FIG.
A hot tapping 13 for taking out the gas for measuring the flow rate from the inside of the pipe and a gas pressure gauge 14 are provided. The hot tapping 13 described above has, as seen in a known gas flow meter (see, for example, Japanese Patent Laid-Open No. 4-2922),
The flow rate detection sensor 15 is hung in the conduit of the medium pressure conduit 2,
The static pressure and dynamic pressure of the gas obtained from this sensor 15 are used for the pressure guiding tube 1
The flow rate measuring means 6 and 17 lead to the flow rate calculator 18 on the ground to calculate the gas flow rate from the pressure difference between the two.

[0005]

When detecting the flow rate of gas, the flow rate detection sensor 15 must be installed in a straight pipe portion having the same length and a required length in order to ensure its accuracy. Therefore, the above regional block valve 11
When the hot tapping 13 and the pressure gauge 14 for detecting the flow rate are provided in the pit 12 for installing the (shutoff valve), the pit 17 must be large in order to secure the span of the straight pipe portion. And the construction cost for constructing the pit becomes expensive. In particular, since the regional block valves 11 are separately provided in front of the district governor 5 which is divided into each consumption area from the governor station 3, the installed number of the regional block valves 11 must exceed several thousand (about 5000) as a whole. Further, there is a problem that the installation cost of the regional block valve 11 becomes enormous.

Therefore, the inventor of the present invention uses a ball valve as a gas shut-off valve, a flow rate detection sensor in a through hole of the valve body, and a flow rate calculation for calculating a gas flow rate based on a signal obtained from the flow rate detection sensor. By providing a means, gas shutoff and flow rate measurement can be achieved by a single valve, which eliminates the need for conventional hot tapping and pressure gauges, thus reducing the size of the pit. We considered a measure to greatly reduce the construction cost required to install the regional block valve.

In this case, since the water vapor and tar components in the gas adhere to the flow rate detection sensor built in the valve body to cause an error, the flow rate detection sensor can be subjected to maintenance work such as cleaning and replacement from outside the ground. It is necessary to consider so that

An object of the present invention is to provide a ball valve in which a flow meter built in the valve body so as to satisfy the above-mentioned demand can be maintained and inspected from outside the ground.

[0009]

In order to achieve the above-mentioned object, the present invention is a valve provided on the conduit of a gas conduit for shutting off gas or adjusting the flow rate, the valve having the same diameter as the inner diameter of the conduit. A spherical valve body having a through hole and a valve body that rotatably supports and houses the valve body around a vertical axis. The through hole of the valve body is positioned coaxially with the gas conduit to allow gas flow. ,
The ball valve for arranging the through hole in the direction perpendicular to the conduit to cut off the gas or adjust the flow rate is provided with the following means.

That is, the ball valve according to the present invention is provided with a sensor for detecting the flow rate of the gas passing through the through hole of the valve body, and measures the gas flow rate based on the signal obtained from the sensor. A passage for communicating with the valve body and the valve body of the ball valve, which is in communication with the through hole of the valve body to pull up the flow rate detection sensor above the valve body, and to communicate with the passage. A hollow chamber for maintenance and inspection is provided above the valve body, and when the valve is closed, the flow rate detection sensor is passed through the passage and pulled up into the hollow chamber while ensuring the flow of gas between the upstream side and the downstream side of the valve body. It is characterized in that the hollow chamber is opened from the outside of the ground so that the flow rate detector can be maintained and inspected. Another feature is that it has means for closing a passage for ensuring gas flow on the upstream side and the downstream side of the valve body when the valve body is emergency closed in the event of a disaster such as an earthquake. .

[0011]

According to the ball valve having such a configuration, the gas shutoff and the flow rate measurement can be achieved by a single valve. Therefore, when the ball valve is used as a regional block valve, Since such hot tapping and pressure gauges are not required and the pit installation space can be made smaller, the pit can be made smaller and the construction cost required to install the regional block valve can be reduced.

When water vapor or tar in the gas adheres to the flow rate detection sensor built in the valve body, the flow rate detection body is pulled up into the hollow chamber through the pulling passage to open the hollow chamber from the outside of the ground. Since the flow rate detection sensor can be maintained and inspected, maintenance work such as cleaning and replacement of the flow meter can be easily performed.

Further, since the pull-up passage formed in the valve body and the valve body is formed above the valve body by communicating with the through hole of the valve body, the pull-up passage and the hollow chamber can be simply opened by closing the valve body. The gas pressure does not spout from the flow rate detection sensor, and the flow rate detection sensor can be pulled up from the through hole without stopping the gas supply.

[0014]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 3 shows a ball valve of the present invention which is used in place of the regional block valve 11 described above, and which has an upstream intermediate pressure conduit 4 a and a downstream intermediate pressure conduit 4 which traverse the inside of the pit 12.
The valve main body 20 is interposed between the valve main body 20 and b. This valve body 2
0 is supported on the bottom of the pit 12 via the base 21,
The medium pressure conduits 4a and 4b are interposed so as to connect the upstream side and the downstream side.

Inside the valve body 20, a spherical valve body 22 is installed as is found in a normal ball valve. The valve body 22 has an upper stem shaft 24 and a lower stem shaft 23 at the upper and lower sides thereof. It is rotatably supported by the valve body 20 via. Further, the valve body 22 is provided with a through hole 25 having the same diameter as the inner diameters of the medium pressure conduits 4a and 4b connected to the valve body 20, and a straight pipe for disposing a flow rate detecting body 34 described later. The span of the part can be shared by the valve body 22. Further, in the valve body 22, the valve is in the open position when the through hole 25 is located in the same direction as the axis of the intermediate pressure conduits 4a and 4b as shown in the figure, and the through hole 25 is located in the intermediate pressure conduits 4a and 4b.
The valve is in the closed position when it is positioned at a right angle to the axis of.

At the top of the valve body 20, flanges 26, 2 are provided.
A gear box 28 is connected via 7, and a worm gear (not shown) is rotated by a rotating operation of a geared motor 30 or a handle 31 attached to the gear box 28.
The upper stem shaft 24 thrustingly supported in the gear box 28
The valve body 22 is rotationally driven by the geared motor 30 or the handle 31 by meshing with the pinion gear 32 fixed to the.

The upper stem shaft 24 is formed as a hollow shaft, and a hollow passage 33 is formed in the shaft core.
Then, in the hollow passage 33, the flow rate detector 34 is provided at the lower end.
And the flow rate detection body 34 is inserted into the valve body 2
It is suspended in the second through hole 25 and comes into contact with the gas flow passing through the through hole 25. A hollow chamber 36 for maintenance and inspection is communicated with the hollow passage 33.
Reference numeral 6 is a vertically long one connected to the top of the gear box 28 and having an opening end located near the ground in the pit 12. The open end is hermetically closed by an upper plate integrated with the signal conversion unit 37 for detecting and measuring the signal obtained from the flow rate detector 34, and can be opened as required.

The signal converter 37 converts a physical signal (for example, a pressure signal) from the flow rate detector 34 into an electric signal, and the flow rate calculator 4 installed on the ground via the signal line 40.
2 are connected. Here, the flow rate calculator 42 is configured as flow rate measuring means for calculating the gas flow rate based on the electric signal from the signal conversion unit 37.

In the hollow passage 33, when the valve body 22 is in the closed position, the inside of the through hole 25 is closed by contacting both ends with the inner surface of the valve body 20, and the hollow passage 33 is also kept from the gas pressure. When the valve body 22 is in the closed state and thus the valve body 22 is in the closed state, no gas is ejected through the hollow passage 33. Therefore, the valve body 22 is closed, the upper plate of the hollow chamber 36 is opened to open the hollow chamber 36, and the flow rate detector 34 is pulled up through the hollow passage 33 into the hollow chamber 36 and attached to the flow rate detector 34. It is possible to perform a maintenance work such as removing water vapor and tar in the generated gas from outside the ground.

Further, the valve body 22 has a required gap with respect to the inner peripheral surface of the valve body 20 which accommodates the valve body 22, and the intermediate pressure conduit 2a on the upstream side is provided through this gap portion 20a even when the valve is closed. With the configuration that secures the gas flow between the downstream side intermediate pressure conduit 2b and the downstream side medium pressure conduit 2b, the maintenance work of the flow rate detector 34 described above can be carried out without hindering the downstream side gas supply.

In the event of a disaster such as an earthquake, when the gas supply is cut off based on a command from the central monitoring center 8, the valve body 22 is rotated by the geared motor 30 to the closed position. , For example the valve body 20,
The ring shutters 43 and 44 provided at the connecting portions with the upstream and downstream intermediate-pressure conduits 2a and 2b are simultaneously operated so that the communication by the gap portion 20a can be closed.

Next, an example in which the flow rate measuring means attached to the ball valve is constituted by a differential pressure type flow meter and an example by which it is constituted by an electric type flow meter will be described with reference to the drawings. FIG. 4 shows an example in which a conventionally known average value Pitot tube 60 is configured in a differential pressure system, and the average value Pitot tube 60 has a dynamic pressure Pitot 62 with many holes and a static pressure. The pitot 61 and the pitot 61 form a double pipe, and the dynamic pressure pipe 51 is connected to the inside of the dynamic pressure pitot 62, and the static pressure pipe 52 is connected to the inside of the static pressure pitot 61. The flow rate of gas is measured from the pressure.

Further, a configuration using an electric type example instead of the above-mentioned differential pressure type example will be specifically described with reference to FIGS. 5 and 6. FIG. 5 is an explanatory diagram showing a configuration of a flow sensor (heat-sensitive type). The flow sensor measures a gas flow velocity by a temperature difference and detects a gas flow rate based on the result. As shown in FIG. 5A, a first thermistor 71, a heater 72, and a second thermistor 73 are arranged on a flat center chip 70. The center chip 70 thus configured is arranged in the center of the flow sensor 74 and installed inside the ball valve, as shown in FIG. 5B. When the gas flows in the direction of the arrow in the figure, the temperature of the second thermistor 73 downstream of the heater 72 becomes higher than the temperature of the first thermistor 71 upstream of the heater 72. It is configured to measure the flow velocity of gas.

FIG. 6 is an explanatory view showing the structure of the Karman vortex sensor, in which the vortex generator 80 is arranged inside the ball valve. Then, as shown in the figure, when gas flows in the direction of the arrow in the figure,
A Karman vortex train is generated downstream of the vortex generator 80, and the gas flow rate is detected by measuring the frequency of the Karman vortex train.

When the electric sensor described with reference to FIGS. 5 and 6 is used, the static pressure line and the dynamic pressure line which are required for the differential pressure type flow meter are unnecessary, and the static pressure line due to the impact due to an earthquake or the like,
There is no concern about gas leakage due to damage to the dynamic pressure line.

[0026]

According to the present invention, as described above, the gas cutoff valve provided in the gas supply conduit is a ball valve, and the ball valve has a valve that hangs down in the through hole of the valve body. Since the flow rate detecting sensor and the flow rate calculating means for calculating the gas flow rate based on the signal obtained from the flow rate detecting sensor are provided, the gas shutoff and the flow rate measurement can be achieved by a single valve. When this ball valve is used as a regional block valve provided in a conventional gas supply system, for example, there is no need to install hot tapping or a pressure gauge as in the conventional system, and the pit where the ball valve is installed is The size can be greatly reduced and the construction cost required to install the regional block valve can be greatly reduced.

Further, when water vapor or tar content in the gas adheres to the flow rate detecting body built in the valve body, the flow rate detecting sensor is passed through the pulling passage to be pulled up into the hollow chamber, and the hollow chamber is opened from outside the ground. Since the flow rate detector can be maintained and inspected, maintenance work such as cleaning and replacement of the flowmeter can be easily performed.

Further, since the pull-up passage formed in the valve body and the valve body is formed above the valve body in communication with the through hole of the valve body, the pull-up passage and the hollow passage can be formed only by closing the valve body. The gas pressure does not eject from the chamber, and the effect that the maintenance work can be performed by pulling up the flow rate detector from within the through hole without stopping the supply of gas is obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a gas supply system.

FIG. 2 is a schematic view showing the installation form of a conventional regional block valve.

FIG. 3 is a vertical sectional view of a ball valve according to the present invention.

FIG. 4 is a sectional view of a flow rate detector using an average value Pitot tube.

FIG. 5 is an explanatory diagram of a flow sensor.

FIG. 6 is an explanatory diagram of a Karman vortex sensor.

[Explanation of symbols]

 1 Factory 2 High-pressure conduit 3 Governor station 4 Medium-pressure conduit 5 District governor 6 Low-pressure conduit 7 Consumer 8 Central monitoring center 10 Emergency shutoff valve 11 Regional block valve 12 Pit 13 Hot tapping 14 Pressure gauge 15 Flow rate detection sensor 16, 17 Impulsive pipe 18 Flow rate calculator 19 Valve 20 Valve body 20a Gap 21 Base 22 Valve body 23 Lower stem shaft 24 Upper stem shaft 25 Through hole 26, 27 Flange 28 Gabox 30 Geared motor 31 Handle 32 Pinion gear 33 Hollow passage 34 Flow rate detector 35 Pipeline 36 Hollow Chamber 37 Signal Converter 40 Signal Line 42 Flow Rate Calculator 43,44 Ring Shatter 51 Dynamic Pressure Pipeline 52 Static Pressure Pipeline 60 Average Value Pitot Pipe 61 Static Pressure Pitot 62 Dynamic Pressure Pitot 70 Center Chip 71 First Thermistor 72 heater 7 The second thermistor 74 flow sensor 80 shedder

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Shinji Kusunoki 1-1, Nikkocho, Fuchu-shi, Tokyo Inside the Japan Steel Works (72) Inventor Yasunari Mukai 1-1, Nikko-cho, Fuchu-shi, Tokyo Nippon Steel Corporation In-house

Claims (2)

[Claims] 1. A valve provided on a conduit of a gas conduit for shutting off gas or adjusting a flow rate, the valve having a spherical valve body having a through hole having the same diameter as an inner diameter of the conduit, and the valve body. It consists of a valve body that is rotatably supported and housed around a vertical axis. The through hole of the valve element is located coaxially with the gas conduit to allow gas flow, and the through hole is located at a right angle to the conduit to block the gas. Alternatively, in the case of a ball valve for adjusting the flow rate, the ball valve is provided with a flow rate detection sensor for a gas passing through the through hole of the valve body, and a signal obtained from the flow rate detection sensor is used as a base. And a flow rate calculating means for measuring a gas flow rate, and the valve body and the valve body of the ball valve have a passage communicating with the through hole of the valve body to pull up the flow rate detection sensor above the valve body. , A hollow for maintenance and inspection in the upper part of the valve body that communicates with the passage When the valve is closed, the flow rate detection sensor is passed through the passage and pulled up into the hollow chamber while ensuring the gas flow between the upstream side and the downstream side of the valve body, and the hollow chamber is opened from the outside of the ground to detect the flow rate. A ball valve for a gas conduit with a built-in flow meter, characterized in that it allows maintenance and inspection of the body. 2. A means for closing a passage for ensuring gas flow on the upstream side and the downstream side of the valve body when the valve body is emergency closed in the event of a disaster such as an earthquake. A ball valve for a gas conduit, which incorporates the flowmeter according to 1.