JP2022015555A - Gas leakage inspection system - Google Patents

Abstract

To provide a gas leakage inspection system with which it is possible to save man-hours in inspecting inner pipes for leakage.SOLUTION: The gas leakage inspection system comprises: an outer pipe P2 to which a gas of prescribed pressure is supplied from a pressure governor 4; a plurality of inner pipes P1 that constitute a gas passage between gas appliances in each user's house and the outer pipe P2; a gas meter 1 provided in the middle of the inner pipes P1; and a monitoring device 3 constituted so as to be capable of communicating with each gas meter 1. The gas meter 1 includes a flow rate measurement unit for measuring a gas flow rate in the inner pipes P1, and a pressure measurement unit for measuring gas pressure in the inner pipes P1. The monitoring device 3 includes a gas leakage assessment unit which, when all of gas appliances are in an unused state in a group G1 composed of a plurality of gas meters 1 to which a gas is supplied through the same pressure governor 4, assesses the presence of gas leakage from the inner pipes P1 where the gas meters 1 in the group G1 are provided, on the basis of the gas pressure measured by all gas meters 1 in the group G1.SELECTED DRAWING: Figure 1

Description

The present invention relates to a gas leak inspection system for city gas.

Each user's house, which is a gas consumer, is equipped with a gas meter to measure the amount of gas consumed. In the case of city gas, gas is supplied from a gas pipe (outer pipe) buried in the road to a gas appliance in the user's house through a gas pipe (inner pipe) in the premises of the user's house. The gas meter is usually installed in the middle of the outdoor inner pipe.

According to Patent Document 1, when an abnormally large gas flow rate is detected, the shutoff valve is closed to shut off the flow path, and then the shutoff valve is opened to use the gas again to open the flow path for a predetermined time. A gas shutoff device (gas meter) configured to determine leakage after the lapse of time is described.

By the way, gas companies are obliged to carry out leak inspections on a regular basis to ensure that there are no leaks in gas pipes (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication No. 2006-118763 Japanese Unexamined Patent Publication No. 2012-20474

Gas companies must regularly inspect gas pipes (inner pipes) installed on the premises of each user's house, but the number of user's houses is very large, and labor saving in leak inspection is desired. It is rare.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a gas leak inspection system capable of saving labor in leak inspection of an inner pipe.

In order to achieve the above object, the gas leak inspection system according to an aspect of the present invention is provided between an outer pipe to which gas of a predetermined pressure is supplied from a pressure regulator, a gas appliance in each user's house, and the outer pipe. A plurality of inner pipes serving as a gas flow path, a gas meter provided in the middle of the inner pipe, and a monitoring device configured to be able to communicate with each of the gas meters are provided, and the gas meter is a gas flow rate in the inner pipe. The monitoring device includes a flow rate measuring unit for measuring gas pressure and a pressure measuring unit for measuring gas pressure in the inner pipe, and the monitoring device is a group consisting of a plurality of gas meters to which gas is supplied through the same pressure regulator. A gas leak in the inner tube provided with the gas meter in the group based on the gas pressure measured by all the gas meters in the group when all the gas appliances are in an unused state. It has a gas leak determination unit that determines the presence or absence.

According to this configuration, it is possible to omit the inspection performed by the inspector at the site using the gas leak investigation device for the inner pipe determined by the gas leak determination unit to have no gas leak. Therefore, it is possible to save labor in the leakage inspection of the inner pipe.

Further, the gas meter is configured to sequentially transmit the gas flow rate and the gas pressure sequentially measured by the flow rate measuring unit and the pressure measuring unit to the monitoring device, and the gas leak determining unit is transmitted from each of the gas meters. Based on the gas flow rate and gas pressure, when the gas flow rate measured by all the gas meters in the group is equal to or less than a predetermined value, it is determined that all the gas appliances are in an unused state, and this determination is made. A gas pressure that is equivalent or substantially equivalent is selected from all the gas pressures measured by the gas meters at the time, and gas leaks to the inner pipe provided with the gas meter that measures the selected gas pressure. If there is a gas pressure that is not selected as the equivalent or substantially equivalent gas pressure, there is a possibility of gas leakage in the inner pipe provided with the gas meter that measures the gas pressure. It may be configured to determine that there is.

Further, when the gas meter determines whether or not the gas appliance is in an unused state based on the gas flow rate sequentially measured by the flow rate measuring unit, and determines that the gas appliance is in an unused state. Information indicating that the gas appliance is in an unused state is transmitted to the monitoring device, and the gas pressure measured by the pressure measuring unit when it is determined that the gas appliance is in an unused state is measured by the gas appliance. Is configured to be transmitted to the monitoring device together with information indicating that the gas is not in use, and the gas leak determination unit is provided with information indicating that the gas appliance is in an unused state from all the gas meters in the group. Is transmitted at the same time, it is determined that all the gas appliances are in an unused state, and the gas equivalent or substantially equivalent from the gas pressures measured by all the gas meters at the time of this determination is determined. It is determined that there is no gas leak in the inner pipe provided with the gas meter that selects the pressure and measures the selected gas pressure, and there is a gas pressure that is not selected as the gas pressure that is equivalent or substantially equivalent. In this case, the inner pipe provided with the gas meter that measures the gas pressure may be configured to determine that there is a possibility of gas leakage.

Further, the gas leak determination unit is the maximum value and the maximum value of the gas pressure within a predetermined allowable range from the gas pressures measured by all the gas meters, or the gas pressure measured by all the gas meters. A gas pressure within the range of a value minus a predetermined permissible value may be configured to be selected as the equivalent or substantially equivalent gas pressure.

Further, the gas meter calculates a gas integrated flow rate value and a gas pressure average value within the predetermined time at predetermined time intervals based on the gas flow rate and the gas pressure measured by the flow rate measuring unit and the pressure measuring unit. , The gas meter information including these calculated values and the calculated time is configured to be transmitted to the monitoring device, and the monitoring device stores the gas meter information transmitted from each of the gas meters for each gas meter. The gas leak determination unit has a unit, and the gas integrated flow rate value calculated by all the gas meters in the group at the same time is equal to or less than a predetermined value based on the gas meter information stored in the information storage unit. At this time, it is determined that all the gas appliances are not in use, the calculated time of the integrated gas flow value at the time of this determination is selected, and the average gas pressure at the selected calculated time is selected. An equivalent or substantially equivalent gas pressure average value is selected, and it is determined that there is no gas leakage in the inner pipe provided with the gas meter for which the selected gas pressure average value is calculated, and at the selected calculation time. If there is a gas pressure average value that is not selected as the gas pressure average value that is equivalent or substantially equivalent, gas leakage is possible in the inner pipe provided with the gas meter that calculates the gas pressure average value. It may be configured to determine that there is a sex.

Further, the gas meter determines whether or not the gas appliance is in an unused state based on the gas flow rate measured by the flow rate measuring unit within the predetermined time at predetermined time intervals, and the gas appliance is not used. When it is determined that the gas appliance is in a state, information indicating that the gas appliance is not in use is generated, gas meter information including the generated information is transmitted to the monitoring device, and the gas meter is measured by the pressure measuring unit. Based on the gas pressure, the gas pressure average value within the predetermined time determined that the gas appliance is not in use is calculated, and the calculated value and the calculated time are included in the gas meter information to the monitoring device. The monitoring device is configured to transmit, and the monitoring device has an information storage unit that stores the gas meter information transmitted from each gas meter for each gas meter, and the gas leak determination unit is stored in the information storage unit. Based on the gas meter information, when the gas meter information of all the gas meters in the group has information indicating that the gas appliance is in the non-use state at the same time, all the gas appliances are in the non-use state. The gas pressure average value that is equivalent or substantially equivalent is selected from all the gas pressure average values at the selected calculated time, and the gas pressure average value at the time of this determination is selected. It is determined that there is no gas leakage in the inner pipe provided with the gas meter for which the gas pressure average value is calculated, and the gas pressure that is not selected as the gas pressure average value that is equivalent or substantially equivalent at the selected calculation time. If an average value exists, it may be configured to determine that there is a possibility of gas leakage in the inner pipe provided with the gas meter for which the gas pressure average value is calculated.

Further, the gas leak determination unit is the maximum of the gas pressure average value within a predetermined allowable range from all the gas pressure average values at the selected calculation time, or the gas pressure average value at the selected calculation time. The gas pressure average value within the range of the value and the value obtained by subtracting a predetermined allowable value from the maximum value may be selected as the gas pressure average value which is equivalent or substantially equivalent.

Further, the outer pipe has a main branch pipe connected to the pressure regulator and a supply pipe connecting the main branch pipe and the inner pipe, and the group is predetermined in the gas flow direction of the same main branch pipe. It may be composed of a plurality of gas meters provided in the inner pipe connected to each of the plurality of supply pipes connected to a portion within the range.

The present invention has the effect of being able to provide a gas leak inspection system capable of saving labor in leak inspection of an inner pipe by having the configuration described above.

FIG. 1 is a diagram showing a schematic configuration of a gas leak inspection system of the present embodiment. FIG. 2 is a diagram showing a schematic configuration of a gas meter and its peripheral portion in the present embodiment. FIG. 3 is a diagram showing an example in which the data of the mean gas pressure value at the time when all the gas appliances are not in use are plotted in all the gas meters in the gas meter group.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following, the same or corresponding elements may be designated by the same reference numerals throughout all the drawings, and the overlapping description thereof may be omitted. Further, the present invention is not limited to the following embodiments.

(Embodiment)
FIG. 1 is a diagram showing a schematic configuration of a gas leak inspection system of the present embodiment. Further, FIG. 2 is a diagram showing a schematic configuration of a gas meter and its peripheral portion in the present embodiment.

Each of the gas leak inspection systems of the present embodiment includes a plurality of gas meters 1 installed in the user's residential land, and a monitoring device 3 configured to be communicable with each gas meter 1.

Each gas meter 1 is a gas meter for city gas. The city gas produced at the city gas factory is supplied to each user's house through a gas pipe buried in the road via a plurality of pressure regulators and the like.

In the example of FIG. 1, the gas (city gas) supplied to the pressure regulator 4 is depressurized to a predetermined pressure by the pressure regulator 4, passes through a gas pipe (outer pipe P2) buried in the road, and is in the user's house. It is supplied to the gas pipe (inner pipe P1) on the premises. The outer pipe P2 has a main branch pipe P21 connected to the pressure regulator 4 and supplied with gas of a predetermined pressure from the pressure regulator 4, and a supply pipe P22 connected to the main branch pipe P21 and having a smaller pipe diameter than the main branch pipe P21. is doing. Each supply pipe P22 is a gas pipe of a portion connecting the main branch pipe P21 and the inner pipe P1 in each user's home premises.

As shown in FIG. 2, the gas that has passed through the inner pipe P1 is supplied to the gas appliances 22 (22a to 22c) at the user's home. Examples of the gas appliances 22a to 22c include a gas stove, a gas fan heater, a water heater, and the like. In this way, one or more gas appliances 22 are connected to the end of the inner pipe P1 via a gas plug (not shown). A gas valve 21 in a normally open state is provided in the middle of the inner pipe P1, and a gas meter 1 is provided on the downstream side thereof.

The gas meter 1 includes a control unit 10, a shutoff valve 11, a flow rate measurement unit 12, a pressure measurement unit 13, an input operation unit 14, a display unit 15, a communication unit 16, and the like. The shutoff valve 11, the flow rate measuring unit 12, and the pressure measuring unit 13 are provided in the inner pipe P1. The shut-off valve 11 can be configured by a solenoid valve whose opening and closing is controlled by the control unit 10, and is in a normally open state.

The flow rate measuring unit 12 is composed of, for example, a known ultrasonic flow meter, measures the gas flow rate at regular time intervals, and outputs the gas flow rate to the control unit 10. The pressure measuring unit 13 has a known pressure sensor, measures gas pressure at regular time intervals, and outputs the gas pressure to the control unit 10.

The input operation unit 14 is composed of various switches and the like, and inputs a signal (operation signal) according to the operation content to the control unit 10. The display unit 15 has, for example, a display device such as a liquid crystal display or an LED lamp, and can display various information. The communication unit 16 is configured to be able to communicate with the monitoring device 3 installed in the monitoring center.

The control unit 10 is composed of a microcomputer, a microcontroller, or the like, and includes a CPU, a memory (ROM, RAM), and the like. By executing the control program stored in the memory by the CPU, the entire gas meter 1 can be controlled. In addition to the control program, various information can be stored in the memory. The control unit 10 may be configured by a single controller that centrally controls, or may be configured by a plurality of controllers that cooperate with each other to perform distributed control. The control unit 10 controls the shutoff valve 11, the display unit 15, and the communication unit 16.

As a known safety mechanism, the control unit 10 is configured to close the shutoff valve 11 when an abnormality is detected based on the gas flow rate measured by the flow rate measuring unit 12, the gas pressure measured by the pressure measuring unit 13, and the like. ing. For example, when a gas with an abnormally large gas flow rate flows, when a gas flows for an abnormally long time, or when there is an abnormal decrease in gas pressure, the control unit 10 presses the shutoff valve 11. close. Further, the gas meter 1 is provided with a seismic sensor (not shown), and when an earthquake of a predetermined seismic intensity or higher occurs, the control unit 10 closes the shutoff valve 11. The procedure of the return operation for opening the shutoff valve 11 is predetermined.

Further, the control unit 10 has a gas integrated flow rate value within a predetermined time (t2) every predetermined time (t2) based on the gas flow rate (instantaneous flow rate) measured by the flow rate measuring unit 12 at regular time (t1) intervals. (Gas usage amount) is calculated, and the average gas pressure within a predetermined time (t2) is calculated every predetermined time (t2) based on the gas pressure measured by the pressure measuring unit 13 at regular time (t1) intervals. calculate. Then, these calculated values are stored in the memory as gas meter information together with the calculated time (calculated time). Then, the control unit 10 causes the communication unit 16 to transmit the gas meter information stored in the memory from the communication unit 16 to the monitoring device 3. The above times t1 and t2 have a relationship of t1 <t2.

As described above, the control unit 10 is configured to repeatedly create gas meter information, store it in a memory, and transmit it from the communication unit 16 to the monitoring device 3. The gas meter information once transmitted is erased from the memory.

The monitoring device 3 is composed of a computer or the like installed in the monitoring center, and includes a control unit 31, a communication unit 32, an information storage unit 33, an input operation unit 34, a display unit 35, and the like. The control unit 31 is composed of a microcontroller and the like, and includes a CPU, a memory (ROM and RAM), and the like. The CPU can control the entire monitoring device 3 by executing the control program stored in the memory. In addition to the control program, various information can be stored in the memory. The control unit 31 may be configured by a single controller that centrally controls, or may be configured by a plurality of controllers that cooperate with each other to perform distributed control.

The communication unit 32 is configured to be able to communicate with the communication unit 16 of each gas meter 1 via a communication network such as the Internet. The information storage unit 33 is a storage medium for storing gas meter information and the like received from each gas meter 1. The input operation unit 34 is composed of a keyboard, a mouse, and the like, and a signal corresponding to the operation of the input operation unit 34 is input to the control unit 31. The display unit 35 is a display device such as a liquid crystal display.

The information storage unit 33 of the monitoring device 3 includes a pressure regulator 4, a main branch pipe P21, a supply pipe P22, an inner pipe P1 and a gas meter from the city gas factory to the gas meter 1 of each user's house, as shown in FIG. Gas conduit map information indicating the position information of 1 is stored. The main branch pipe P21 may be branched into a plurality of branches.

Further, the information storage unit 33 sequentially stores the gas meter information sequentially transmitted from each gas meter 1 for each gas meter 1. For example, the communication unit 16 of each gas meter 1 transmits gas meter information together with the identification information of the gas meter 1 (for example, the serial number of the gas meter 1) to the monitoring device 3, and the monitoring device 3 transmits the gas meter information received by the communication unit 32 to the gas meter. By storing the gas meter information in the information storage unit 33 in association with the identification information of 1, the gas meter information can be stored for each gas meter 1. Therefore, the information storage unit 33 stores a large amount of gas meter information generated in a predetermined time (t2) for each gas meter 1.

Next, a leak inspection of the inner pipe P1 of each user's house by the gas leak inspection system of the present embodiment will be described.

In this gas leak inspection system, for example, the operator of the monitoring device 3 performs a predetermined operation (inspection start operation) on the input operation unit 34 to input the inspection start signal to the control unit 31.

When the inspection start signal is input, the control unit 31 functions as a gas leak determination unit and performs a gas leak determination process. In this gas leak determination process, the inner pipe P1 provided is stored in the information storage unit 33 in the gas meter group consisting of a plurality of gas meters 1 connected to the same pressure regulator 4 via the supply pipe P22 and the main branch pipe P21. When the integrated gas flow value calculated by all the gas meters 1 in the gas meter group at the same time (same calculation time) is equal to or less than the predetermined value (F) based on the gas meter information, all the gas appliances 22 are not in use. And select the calculated time when this judgment is made. The predetermined value (F) is set to a value smaller than the minimum integrated flow rate value within the predetermined time (t2) when the gas appliance 22 of the type having the minimum gas usage amount is used, for example.

Next, the control unit 31 has the same or substantially the same gas pressure average value (details will be described later) from all the gas pressure average values at the selected calculated time. Hereinafter, it is also referred to as "normal value"). Then, it is determined that there is no gas leak in the inner pipe P1 provided with the gas meter 1 for which the gas pressure average value selected as the normal value (equal or substantially equivalent gas pressure average value) is calculated.

As the above gas meter group, for example, a group consisting of all gas meters 1 in the chain line G1 shown in FIG. 1 (hereinafter, referred to as “gas meter group G1”) can be exemplified. Here, when the leak inspection of the inner pipe P1 of each user's house is performed by the gas leak inspection system of the present embodiment, the internal shutoff valve 11 and the external gas valve 21 of all the gas meters 1 in the gas meter group G1 are usually used. It is a state, that is, an open state.

Each supply pipe P22 connected to each inner pipe P1 is connected to a main branch pipe P21 having a larger diameter than this, and gas of a predetermined pressure is supplied to the main branch pipe P21 from the pressure regulator 4. There is. Therefore, it is considered that the gas pressures of the inner pipes P1 measured by each gas meter 1 have almost no influence on each other (very small). That is, when there is no gas leak, the gas pressure of each inner pipe P1 measured by each gas meter 1 fluctuates mainly according to the usage state of the gas appliance 22 connected to each inner pipe P1.

For example, in a certain gas meter group G1, at a time when all gas appliances 22 connected to each inner pipe P1 are not in use (referred to as time tx), gas leaks to all inner pipes P1 and supply pipes P22. Without it, the gas pressure average values of all gas meters 1 are equal or substantially equal.

Therefore, the control unit 31 has a predetermined gas integrated flow rate value calculated by all the gas meters 1 in the gas meter group G1 at the same time (same calculation time) based on the gas meter information stored in the information storage unit 33. F) In the following cases, it is determined that all the gas appliances 22 are in an unused state, the calculated time at the time of this determination (the time tx in the above-mentioned unused state) is selected, and all the gas appliances 22 in the selected calculated time are selected. A gas meter 1 in which a normal value (equal or substantially equivalent gas pressure average value) is selected from the gas pressure average values based on a predetermined normal value selection condition, and the gas pressure average value selected as the normal value is calculated. The gas leak determination process is performed so that it is determined that there is no gas leak in the inner pipe P1 provided with the above.

On the other hand, if a gas leak occurs in any of the inner pipes P1 (for example, the location B1 in FIG. 1) at the time tx in the unused state, it is calculated by the gas meter 1 provided in the inner pipe P1. The average gas pressure value is lower than the average gas pressure value calculated by the gas meter 1 provided in the inner pipe P1 where no other gas leak has occurred.

Therefore, in the gas leak determination process, if there is a gas pressure average value that is not selected as a normal value at the time tx in the non-use state, the control unit 31 uses the gas meter 1 to calculate the gas pressure average value. It may be determined that there is a possibility of gas leakage in the provided inner pipe P1. Here, it is determined that there is a possibility of gas leakage because there is no gas leakage in the inner pipe P1 and there is a gas leak in the supply pipe P22 connected to the inner pipe P1.

When the gas leak determination process is completed, the control unit 31 stores the determination result in the information storage unit 33 and displays the determination result on the display unit 35 to notify the operator. The method of displaying the determination result is not particularly limited, and for example, the determination result may be displayed on the display unit 35 by superimposing the determination result on the gas conduit map information described above.

Next, the normal value selection condition will be described. As the normal value selection condition, for example, the following conditions (1) or (2) can be used.
(1) Select the gas pressure mean value within the specified allowable range as the normal value.
(2) Select the gas pressure average value within the range of the maximum value of the gas pressure average value at the time tx in the unused state and the value obtained by subtracting the predetermined allowable value from this maximum value as the normal value.

The condition (1) and the condition (2) above will be described with reference to FIG. FIG. 3 is a diagram showing an example in which data of gas pressure mean values at time tx (time when all gas appliances are not in use) of all gas meters 1 in the gas meter group G1 are plotted. M1, M2, M3, ..., Mn on the horizontal axis indicate the gas meter 1, respectively.

In the case of the condition (1) above, a predetermined allowable range Dr in which the lower limit value is Pa and the upper limit value is Pb is predetermined, and the gas pressure average value within this allowable range Dr is set as a normal value. In the example of FIG. 3, the gas pressure mean value of the gas meter 1 other than M3 is a normal value. The allowable range Dr is set so that the average gas pressure within the range is recognized to be substantially equivalent.

The case of the above condition (2) will be described. In the example of FIG. 3, the maximum value of the gas pressure average value is the gas pressure average value (Pm) of the gas meter 1 of Mn. The value obtained by subtracting the predetermined allowable value (d) from the maximum value (Pm) is Pm−d.

Therefore, in the case of the condition (2), the average gas pressure within the range Ds of (Pm−d) or more and Pm or less is set as the normal value. In the example of FIG. 3, the gas pressure mean value of the gas meter 1 other than M3 is a normal value. The magnitude of the permissible value (d) is set so that it is recognized that the gas pressure average value within the range Ds of the magnitude is substantially equivalent.

Further, as another example of the normal value selection condition, the median value (Pc) of all the gas pressure mean values at the time tx in the unused state is obtained, and for example, using a positive predetermined value e, (Pc-e). ) And above, the gas pressure mean value within the range of (Pc + e) or less may be set as a normal value.

In the present embodiment, for the inner pipe P1 determined by the control unit 31 (gas leak determination unit) that there is no gas leak, an inspector goes to the site (user's house) and conducts an inspection using a gas leak investigation device. It can be omitted. Therefore, it is possible to save labor in the leakage inspection of the inner pipe.

In the above, the group G1 is exemplified as the gas meter group, but the group G1 is not limited to this, and for example, a group consisting of all the gas meters 1 in the chain line G2 shown in FIG. 1 (hereinafter referred to as “gas meter group G2”) can be exemplified. .. This gas meter group G2 is composed of a plurality of gas meters 1 provided in an inner pipe P1 connected to each of a plurality of supply pipes P22 connected to a portion within a predetermined range R1 in the gas flow direction of the same main branch pipe P21. There is. In this case, a plurality of gas meter groups G2 are set in the group G1. In this way, the gas meter group can be changed in various ways. The control unit 31 functions as a gas leak determination unit that performs the above-mentioned gas leak determination process for each gas meter group. The smaller the number of gas meters 1 constituting the gas meter group, the easier it is to select the time tx when all the gas appliances 22 are not in use.

The information of the gas meter group may be stored in advance in the information storage unit 33 together with the gas conduit map information. Further, for example, the gas conduit map information may be displayed on the display unit 35, and the gas meter group may be set by operating the input operation unit 34.

In the above example, the monitoring device 3 determines whether or not the gas appliance 22 is in an unused state based on the gas integrated flow rate value of the gas meter information obtained from each gas meter 1, but each gas meter. 1 may make a judgment. In this case, each gas meter 1 determines whether or not the gas appliance 22 is in an unused state based on the gas flow rate measured within a predetermined time (for example, when the gas flow rate is equal to or less than a predetermined value, the gas appliance 22 determines. (Determined to be in an unused state), when it is determined to be in an unused state, information indicating that the gas appliance is in an unused state is generated, and gas meter information including this generated information is transmitted to the monitoring device 3. At the same time, the gas pressure average value within a predetermined time when it is determined that the gas appliance is not in use is calculated, and the calculated value and the calculated time are included in the gas meter information and transmitted to the monitoring device 3. , The monitoring device 3 determines that all the gas appliances are in the non-use state when the gas meter information of all the gas meters 1 in the gas meter group contains information indicating that the gas appliances are not in use at the same time. It may be configured as follows.

In the above example, the monitoring device 3 performs the gas leak determination process based on a large number of gas meter information stored in the information storage unit 33 for each gas meter 1, but another example described below. You may do it like this.

[Other examples]
In another example, the gas leak determination process is performed using the gas flow rate and gas pressure measured by the flow rate measuring unit 12 and the pressure measuring unit 13 instead of the gas integrated flow rate value and the gas pressure average value described above. To do so.

In this case, for example, when the operator of the monitoring device 3 performs an inspection start operation on the input operation unit 34, the monitoring device 3 performs a flow rate measuring unit 12 and a pressure measuring unit for all the gas meters 1 in the gas meter group. Instruct to transmit the gas flow rate and gas pressure measured at regular time (t1) intervals at 13. Here, the gas meter 1 may sequentially transmit each time the gas flow rate and the gas pressure are measured, or the transmission interval (interval of a plurality of times t1) is determined in advance and the measurement is performed at the transmission interval. The gas flow rate and gas pressure may be sequentially transmitted.

Then, the control unit 31 (gas leak determination unit) of the monitoring device 3 determines the gas flow rate measured by all the gas meters 1 in the gas meter group based on the gas flow rate and the gas pressure transmitted from each gas meter 1. When it is equal to or less than the value, it is judged that all the gas appliances 22 are in an unused state, and the gas pressure equivalent or substantially equivalent is selected from the gas pressures measured by all the gas meters 1 at the time of this judgment. It is determined that there is no gas leak in the inner pipe P1 provided with the gas meter 1 that measures the selected gas pressure. Further, when there is a gas pressure that is not selected as an equivalent or substantially equivalent gas pressure among all the gas pressures measured by all the gas meters 1 when it is determined that all the gas appliances 22 are not in use. May determine that there is a possibility of gas leakage in the inner pipe P1 provided with the gas meter 1 that measures the gas pressure.

The above-mentioned equivalent or substantially equivalent gas pressure may be a gas pressure within a predetermined allowable range from the gas pressures measured by all the gas meters 1, or the gas pressure measured by all the gas meters 1. The gas pressure may be within the range of the maximum value of and the value obtained by subtracting a predetermined allowable value from this maximum value. Alternatively, the median value (Pf) of the gas pressure measured by all the gas meters 1 is obtained, and for example, using a positive predetermined value g, a gas in the range of (Pf−g) or more and (Pf + g) or less. It may be pressure.

The gas pressure may be corrected by the altitude at which the gas meter is installed, or may be corrected by the temperature of the gas detected by the temperature detection unit (not shown) provided in the gas meter.

Since the integrated gas flow rate value and the gas pressure average value in the above-mentioned example are calculated based on the measured gas flow rate and gas pressure, respectively, the gas leak determination process is performed on the gas in the above-mentioned example as well. It is based on the flow rate and gas pressure.

In the other example described above, each gas meter 1 determines whether or not the gas appliance 22 is in an unused state based on the measured gas flow rate (for example, when the gas flow rate is equal to or less than a predetermined value, the gas appliance 22 is not used. It may be determined that 22 is in an unused state). In this case, when the gas meter 1 determines that the gas appliance is in an unused state, the gas meter 1 generates information indicating that the gas appliance is in the unused state, and transmits the measured gas pressure together with the generated information to the monitoring device 3. When the information indicating that the gas appliance is not in use is transmitted from all the gas meters 1 in the gas meter group at the same time (including almost the same time), the monitoring device 3 is configured as such. The device may be configured to determine that it is in an unused state.

From the above description, many improvements and other embodiments of the present invention will be apparent to those skilled in the art. Therefore, the above description should be construed as an example only and is provided for the purpose of teaching those skilled in the art the best aspects of carrying out the present invention. The details of its structure and / or function can be substantially changed without departing from the spirit of the present invention.

The present invention is useful as a gas leak inspection system or the like that can save labor in leak inspection of an inner pipe.

P1 Inner pipe P2 Outer pipe P21 Main branch pipe P22 Supply pipe G1, G2 Gas meter Group 1 Gas meter 3 Monitoring device 4 Pressure regulator 10 Control unit 12 Flow rate measurement unit 13 Pressure measurement unit 14 Input operation unit 15 Display unit 16 Communication unit 22a to 22c Gas Instrument 31 Control unit 32 Communication unit 33 Information storage unit

Claims (8)

An outer pipe to which gas of a predetermined pressure is supplied from a pressure regulator, a plurality of inner pipes serving as a gas flow path between the gas appliance in each user's house and the outer pipe, and a gas meter provided in the middle of the inner pipe. And a monitoring device configured to communicate with each of the gas meters.
The gas meter is
It has a flow rate measuring unit that measures the gas flow rate in the inner pipe and a pressure measuring unit that measures the gas pressure in the inner pipe.
The monitoring device is
Based on the gas pressure measured by all the gas meters in the group when all the gas appliances are in a non-use state in the group consisting of the plurality of gas meters to which gas is supplied through the same pressure regulator. The gas leak determination unit for determining the presence or absence of gas leakage in the inner pipe provided with the gas meter in the group is provided.
Gas leak inspection system. The gas meter is
It is configured to sequentially transmit the gas flow rate and gas pressure sequentially measured by the flow rate measuring unit and the pressure measuring unit to the monitoring device.
The gas leak determination unit is
Based on the gas flow rate and gas pressure transmitted from each of the gas meters, when the gas flow rate measured by all the gas meters in the group is equal to or less than a predetermined value, all the gas appliances are in an unused state. The gas meter provided is provided with a determination, selecting a gas pressure equivalent or substantially equivalent from all the gas pressures measured by the gas meters at the time of this determination, and measuring the selected gas pressure. If it is determined that there is no gas leakage in the inner pipe and there is a gas pressure that is not selected as the equivalent or substantially equivalent gas pressure, the inner pipe provided with the gas meter that measures the gas pressure Was configured to determine that there was a possibility of gas leakage,
The gas leak inspection system according to claim 1. The gas meter is
It is determined whether or not the gas appliance is in an unused state based on the gas flow rate sequentially measured by the flow rate measuring unit, and when it is determined that the gas appliance is in an unused state, the gas appliance is not used. Information indicating the state is transmitted to the monitoring device, and the gas pressure measured by the pressure measuring unit when it is determined that the gas appliance is not in use is not used in the gas appliance. It is configured to be transmitted to the monitoring device together with the information indicating that.
The gas leak determination unit is
When information indicating that the gas appliance is not in use is transmitted from all the gas meters in the group at the same time, it is determined that all the gas appliances are in the unused state, and this determination is made. A gas pressure that is equivalent or substantially equivalent is selected from all the gas pressures measured by the gas meters at the time, and a gas leak is provided to the inner pipe provided with the gas meter that measures the selected gas pressure. If there is a gas pressure that is not selected as the equivalent or substantially equivalent gas pressure, there is a possibility of gas leakage in the inner pipe provided with the gas meter that measures the gas pressure. Configured to determine that there is,
The gas leak inspection system according to claim 1. The gas leak determination unit is
The gas pressure within a predetermined allowable range from the gas pressures measured by all the gas meters, or the maximum value of the gas pressure measured by all the gas meters and the predetermined allowable value were subtracted from this maximum value. A gas pressure within the range of the value is configured to be selected as the gas pressure equivalent or substantially equivalent.
The gas leak inspection system according to claim 2 or 3. The gas meter is
Based on the gas flow rate and gas pressure measured by the flow rate measuring unit and the pressure measuring unit, the integrated gas flow rate value and the gas pressure average value within the predetermined time are calculated at predetermined time intervals, and these calculated values are obtained. And gas meter information including the calculated time is configured to be transmitted to the monitoring device.
The monitoring device is
It has an information storage unit that stores the gas meter information transmitted from each of the gas meters for each gas meter.
The gas leak determination unit is
When the integrated gas flow value calculated by all the gas meters in the group at the same time based on the gas meter information stored in the information storage unit is equal to or less than a predetermined value, all the gas appliances are in a non-use state. Select the calculated time of the gas integrated flow value at the time of this determination, and select the equivalent or substantially equivalent gas pressure average value from all the gas pressure average values at the selected calculated time. Then, it is determined that there is no gas leakage in the inner pipe provided with the gas meter for which the selected gas pressure average value is calculated, and at the selected calculation time, the gas pressure average value is equivalent or substantially equivalent. If there is a gas pressure average value that is not selected as, it is configured to determine that there is a possibility of gas leakage in the inner pipe provided with the gas meter that calculated the gas pressure average value.
The gas leak inspection system according to claim 1. The gas meter is
Every predetermined time, it was determined whether or not the gas appliance was in an unused state based on the gas flow rate measured by the flow rate measuring unit within the predetermined time, and it was determined that the gas appliance was in an unused state. Occasionally, information indicating that the gas appliance is not in use is generated, and gas meter information including this generated information is transmitted to the monitoring device and at the same time.
Based on the gas pressure measured by the pressure measuring unit, the gas pressure average value within the predetermined time determined that the gas appliance is not in use is calculated, and the calculated value and the calculated time are set to the gas meter. It is configured to be included in the information and transmitted to the monitoring device.
The monitoring device is
It has an information storage unit that stores the gas meter information transmitted from each of the gas meters for each gas meter.
The gas leak determination unit is
Based on the gas meter information stored in the information storage unit, all when the gas meter information of all the gas meters in the group contains information indicating that the gas appliance is in an unused state at the same time. It is determined that the gas appliance is not in use, the calculated time at the time of this determination is selected, and the gas pressure average value that is equivalent or substantially equivalent from all the gas pressure average values at the selected calculated time. Is selected, and it is determined that there is no gas leak in the inner pipe provided with the gas meter for which the selected gas pressure average value is calculated, and the gas pressure is equivalent or substantially equivalent at the selected calculation time. If there is a gas pressure average value that is not selected as the average value, it is configured to determine that there is a possibility of gas leakage in the inner pipe provided with the gas meter that calculated the gas pressure average value. ,
The gas leak inspection system according to claim 1. The gas leak determination unit is
The gas pressure average value within a predetermined allowable range from all the gas pressure average values at the selected calculated time, or the maximum value of the gas pressure average value at the selected calculated time and the predetermined allowable value from this maximum value. A gas pressure mean value within the range of the value subtracted from the value is configured to be selected as the equivalent or substantially equivalent gas pressure mean value.
The gas leak inspection system according to claim 5 or 6. The outer tube is
It has a main branch pipe connected to the pressure regulator and a supply pipe connecting the main branch pipe and the inner pipe.
The group
It is composed of a plurality of gas meters provided in the inner pipe connected to each of the plurality of supply pipes connected to a portion within a predetermined range in the gas flow direction of the same main branch pipe.
The gas leak inspection system according to any one of claims 1 to 7.

Images