JP2002364776A - Gas pipe replacement construction method - Google Patents

Abstract

(57) [Abstract] [Problem] While ensuring safety in gas pipe replacement work,
Provided is a gas pipe replacement construction method capable of simplifying an ignition test of gas appliances in each dwelling unit of an apartment house. In a gas pipe replacement method according to the present invention, after a lamp outer tube connecting a main pipe and a standpipe in a pipe shaft of an apartment house is replaced, the gas pipe is replaced at a connection position between the lamp outer pipe and a standpipe in the pipe shaft. The air purge is performed only at the nearest (most upstream) gas meter section. By performing the air purge at the gas meter section at the most upstream, there is almost no residual air in the gas pipe in the apartment house, and the ignition test on the dwelling units of the gas meters other than the gas meter on which the air purge has been performed becomes unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for replacing gas pipes, and more particularly to an air purge process for removing air from a new gas pipe after replacement of a gas pipe. The present invention relates to a gas pipe replacement construction method capable of simplifying an ignition test of a gas appliance.

[0002]

2. Description of the Related Art FIG. 4 is a view for explaining a conventional gas exchange construction method. As shown in FIG. 4, a lamp outer tube 2 extends from a main pipe 1 buried underground to a ground to an apartment house 10 under the ground, and the lamp outer pipe 2 is located in a pipe shaft immediately below the apartment house. It is connected to the tube 3a. When a plurality of pipe shafts are provided in an apartment house as shown in the figure, the lamp outer tube 2 is connected to the standing pipe 3a in each of the pipe shafts. From the standing pipe 3a in each pipe shaft, a branch pipe 3b is drawn into each dwelling unit via the gas meter M for each of the plurality of dwelling units constituting the apartment house.

A main pipe 1 and a standpipe 3a in a pipe shaft
When the lamp outer tube 2 connecting the lamps deteriorates over time, replacement work is performed. In this lamp outer tube replacement work,
Prior to the construction, first, a request is made to each dwelling unit of the apartment house into which the lamp outer tube 2 is to be drawn in for the construction in advance and to be at home at the time of completion of the construction on a flyer or the like. Then, on the day of the construction, after replacing the old lamp outer tube 2 with the new lamp outer tube 2, a process (air purge) for bleeding air from the new lamp outer tube is performed at a previously selected location.

A plurality of air purging points P are selected for each pipe shaft. For example, a plurality of gas meters, such as a gas meter closest (upstream) to the replaced lamp outer tube 2, a gas meter farthest (downstream), and a gas meter therebetween. A gas meter is arbitrarily selected. Then, for each of the selected gas meters, a connection point between the gas pipe M and the branch pipe 3b branched from the standing pipe 3a in each pipe shaft is removed, and the air is removed therefrom. After that, in all dwelling units,
Persons involved in construction work (including gas company personnel) to prevent gas equipment from being burned out and extinguished due to residual air in gas pipes (including the vertical pipe 3a and the branch pipe 3b in the pipe shaft) in the apartment house Visited each dwelling unit and conducted an ignition test of gas appliances in the dwelling unit.

[0005] At this time, with regard to the unoccupied dwelling unit, the person in charge of construction waits for the resident to return home until a specific time, and thereafter, "contacts the gas company before using gas appliances, conducts an ignition test by the gas company" Distribute a flyer to request and take over the duties to the duties staff of a gas company. When receiving a notification from a resident who has been absent, the duties worker of the gas company is dispatched to the dwelling unit for an ignition test at any time, and conducts an ignition test for all the units.

[0006]

However, even if a flyer for requesting to stay at home on the day of construction is distributed, a considerable number of people are not at home and a specific time (for example, 19
It was very difficult to complete the ignition test for all units within (hour). Accordingly, the burden on the absentee housing personnel (nightkeepers of the gas company) and the cost thereof are increased, and the efficiency of construction is hindered. In addition, due to the diversification of life time in recent years, there is a demand for a gas pipe replacement construction method on the premise that a considerable number of absent persons are present.

Accordingly, an object of the present invention is to provide a gas pipe replacement construction method capable of simplifying an ignition test of gas appliances in each dwelling unit of an apartment house while securing safety in gas pipe replacement work. It is in.

[0008]

In order to achieve the above object, in the gas pipe replacement method according to the present invention, after replacing a lamp outer tube connecting a main pipe and a standing pipe in a pipe shaft of an apartment house, the gas pipe replacement method is performed. The air purge is performed only at the gas meter portion closest to the connection position between the pipe and the standing pipe in the pipe shaft (upstream).

[0009] By performing the air purge at the most upstream gas meter portion, there is almost no residual air in the gas pipes in the apartment house, and it is not necessary to perform an ignition test on the dwelling units of the gas meters other than the gas purged gas meter. Become.

For example, the gas pipe replacement construction method of the present invention for achieving the above object provides at least one first gas pipe (a standing pipe in a pipe shaft) drawn into each of a plurality of dwelling units constituting an apartment house. And a second gas pipe extending outside the apartment house (light tube), the second gas pipe is separated from the first gas pipe and the old gas pipe is separated from the old gas pipe. Replace with a new gas pipe, from the connection portion with the first gas pipe in the first gas meter closest to the new gas pipe among all the plurality of gas meters for each dwelling unit connected to the first gas pipe, An air purge for removing air in the new gas pipe is performed.

The nearest unit of the gas meter is:
In the case of absence on the day of the construction, among the gas meters of the dwelling units at home on the day of the construction, at the connection between the gas meter closest to the new gas pipe and the first gas pipe, to bleed the air in the new gas pipe Is performed.

[0012] After the air purge is performed, an ignition test of a gas appliance in the dwelling unit corresponding to the nearest gas meter is always performed by a person in charge of construction.

[0013] Regarding the ignition test of the gas appliance in the dwelling unit corresponding to the gas meter other than the closest gas meter, the resident of each dwelling unit is requested to carry out the ignition test, and the person in charge of construction does not carry out the test.

[0014] Alternatively, the ignition test of the gas appliances in the dwelling unit corresponding to the gas meter other than the closest gas meter is carried out by a construction-related person for the dwelling unit at home before a specific time has passed. For a dwelling unit that is absent even after a specific time has passed, a request may be made to the resident of each dwelling unit.

In the case where the apartment house has a plurality of first gas pipes, each of the first gas pipes has a plurality of gas meters connected to the first gas pipes. In a gas meter of a certain dwelling unit, at a connection portion between the gas meter closest to the new gas pipe and the first gas pipe,
An air purge is performed to remove the air in the new gas pipe.

When the time for disconnecting the second gas pipe from the first gas pipe is a predetermined time or more, the second gas pipe closest to the new gas pipe among the gas meters on the upper floor of the first gas meter. The air purge may also be performed at the portion of the gas meter connected to the first gas pipe.

[0017]

Embodiments of the present invention will be described below. However, the technical scope of the present invention is not limited to the present embodiment.

FIG. 1 is a view for explaining an outline of a gas pipe replacement work method according to an embodiment of the present invention. In the gas pipe replacement method according to the embodiment of the present invention, the main pipe 1
After the replacement of the lamp outer tube 2 connecting the pipes 3a in the pipe shaft of the apartment house 10, an air purge point for bleeding air in the new lamp outer tube 2 is set up in the lamp pipe 2 and the pipe in the pipe shaft. A gas meter portion (position P1 in FIG. 1) closest to the connection position with 3a (most upstream).

As will be described in detail below, the present inventors carry out air purging from a connection portion (hereinafter, sometimes referred to as a gas meter portion) between the most upstream gas meter M and the branch pipe 3b, so that the air is purged further downstream (hereinafter, referred to as a gas meter portion). Gas pipes (including a vertical pipe 3a and a branch pipe 3b in a pipe shaft) in a collective house of a direction away from the lamp outer pipe and including a direction of an upper floor along a vertical pipe 3a in a pipe shaft. ) Was found to have very little air left.

From this, an air purge operation is performed only at the most upstream gas meter portion, that is, at a position where the branch pipe 3b and the gas meter M are removed, and thereafter,
For the most upstream gas meter dwelling unit, the person in charge of construction (the person in charge of the gas company) always conducts an ignition test on the gas equipment, and for other dwelling units, gas pipes that do not necessarily require an ignition test by the person in charge of construction. A replacement construction method was devised.

With respect to the gas meter on which the air purge has been performed, the gas meter M is connected to the branch pipe 3 to perform the air purge.
Since it is removed from b, there is a possibility that air may enter the gas meter from there, and an ignition test of the gas appliance in the dwelling unit of the gas meter M is necessarily required. On the other hand, for gas meters of other dwelling units in the apartment complex, the air purge is not performed, and there is almost no residual air in the gas pipes in the apartment complex. Because it is close to zero, the residents decided to request an ignition test using a flyer or the like.

As described above, according to the gas pipe replacement method according to the embodiment of the present invention, the air purge after the replacement of the lamp outer tube is performed only at the gas meter (most upstream gas meter) closest to the lamp outer tube. As a result, there is almost no residual air in the gas pipes downstream of the gas pipes (particularly, standing pipes and branch pipes in the pipe shaft), so that it is not necessary to perform air purging at a plurality of locations. There is no need for an ignition test by a person involved in the construction of the gas meter at a dwelling unit other than the dwelling unit. As a result, the burden of the ignition test by the persons involved in the construction is greatly reduced, and the efficiency of the construction and the labor costs can be reduced.

A description will be given below of the results of a survey performed when an air purge operation was performed in the gas pipe replacement method according to the embodiment of the present invention and an ignition test was performed on all the units.

Contents of the survey (1) Target: Reinforced apartment house with 15 or more gas meters in principle (2) Method: After replacing the lamp, replace the pipe shaft of each apartment house with the gas meter from the uppermost stream. After performing the air purge, an ignition test was performed on all the houses, and the state of the combustion flame at that time was observed. (3) Number of surveys: 190 buildings, 6 pipe shafts
60, 5420 gas meters (4) Survey results

[0025]

[Table 1]

(5) Verification result: In a dwelling unit from which the gas meter and the gas pipe were removed for air purging, the burning flame was extinguished at the time of the ignition test with a probability of 94.5%, but the other gas meters were not removed. About, there was no disappearance. As described above, most of the gas meter dwelling units for which the air purging was not performed did not go out, and it was confirmed that sufficient safety could be ensured by the ignition test by the residents themselves.

Next, the results of a gas analysis test using a building to be removed will be described.

Details of the survey (1) Target: 4-story reinforced steel building (24 units in total, one of which is closed), lamp tube diameters 50A and 40A (2) Contents: Pipe shaft A in the gas pipe diagram of FIG. , C, the most upstream gas meter closest to the replaced lamp outer tube, and for the pipe shaft B, the most downstream gas meter was selected as the air purge point P, and air purging was performed. After the air purge, the gas was sampled from each sampling position S shown in FIG. 2, and the composition was analyzed by gas chromatography. After sampling the gas, an ignition test was performed at each dwelling unit. (3) Analysis result: The concentration of the gas sampled at each sampling position in FIG. 2 is shown. (4) Verification result: After the air purge, the gas composition analysis results at each position in FIG. 2 indicate that the gas concentration is 80% or more at any sampling position, and that the gas composition is sufficient to maintain normal combustion. Met. However, as shown in the figure, the gas concentrations in the pipe shafts A and C for which the air purge was performed by the uppermost stream gas meter were 90% at all sampling positions, and almost half of the gas concentrations were 99% or more. It was confirmed that there was no residual air. On the other hand, the gas concentration in the pipe shaft B was a concentration necessary to maintain normal combustion, but was lower than the gas concentration in the pipe shafts A and C. It was confirmed that the air purge was more preferable because the residual air was smaller.

From the above investigation results, after replacing the lamp outer tube, for each pipe shaft of the apartment house, an air purge is performed at one of the gas flow sections at the most upstream position, and after the air purge is carried out, the air is purged at the dwelling unit of the most upstream gas meter. Only for this, an ignition test was conducted by a person in charge of construction (a person in charge of the gas company).

This eliminates the need for the gas company staff to conduct an ignition test on all the units in the apartment house, simplifying the ignition test process while ensuring safety, and improving the efficiency and time of the entire construction. Can be In addition, it is not necessary to ask all the units to stay at home, and the burden on residents can be reduced.

FIG. 3 is a processing flowchart of the gas pipe replacement work method according to the embodiment of the present invention. In FIG. 3, first, a leaflet for performing a construction for replacing a gas pipe is distributed to all the houses (S10). Then, the person in charge of the gas company hears and investigates the home situation on the day of the construction in advance (S11), and determines the air purge location after the replacement of the lamp outer tube (S12). Specifically, as described above, the air purge execution point is, for each pipe shaft of an apartment house, the gas flow portion that is closest to the lamp outer tube to be replaced. If the resident of the gas meter's dwelling unit is at home on the day of construction, the most upstream gas meter is determined as the air purge location. Generally, the most upstream gas meter is a gas meter of a dwelling unit adjacent to a pipe shaft on the first floor of an apartment house. Also,
If the resident of the dwelling unit of the most upstream gas meter is absent on the day of the construction, the gas meter closest to the light bulb among the gas meters of the dwelling units at home is determined as the air purge point.

It should be noted that, after the air purge is performed, the fact that an ignition test is to be performed in the dwelling unit is informed to the dwelling unit of the gas meter determined to be the air purging location.

On the day of construction, the lamp outer tube is cut off from the main tube and replaced with an old lamp outer tube with a new lamp outer tube (S13).
After replacement of the lamp outer tube, air purging is performed at the gas meter portion, which is the air purging location determined in step S12 (S14).

After performing the air purging, in step S15, it is necessary to always perform an ignition test by a person related to the construction of the dwelling unit of the gas meter for which the air purging has been performed. ) To (S16), the person in charge of the gas company, who is a construction-related person, confirms that the resident of the dwelling unit of the air purge execution gas meter is at home (S17), and performs an ignition test of the gas equipment (S1).
8). In step S11, it was confirmed in advance that the gas consumer of the air purge execution gas meter was at home on the day of construction, but it may be absent due to a subsequent schedule change or urgent business. Therefore, if the resident is absent even after the specified time, a flyer for requesting “contacting the gas company before using the gas equipment and conducting an ignition test by the gas company” is distributed (S19), The duties are taken over by the duties of a gas company (S20). When receiving a notification from a resident who has been absent, the night worker of the gas company is dispatched to the dwelling unit for an ignition test and performs an ignition test.

On the other hand, in step S15, for the dwelling units of other gas meters for which air purging has not been performed,
Although an ignition test by a person involved in construction is not necessarily required, in the embodiment of FIG. 3, for a dwelling unit that is at home by a specific time (S21, S22), an ignition test by a person involved in construction is performed (S23). .

A flyer for requesting an ignition test by the resident is distributed to the resident who is absent even after the specified time (S24), and the person involved in the construction does not carry out the ignition test.

In this way, it is not necessary to perform an ignition test on a resident who is absent even after a specific time, so that the burden on construction personnel is significantly reduced, which also contributes to a reduction in construction costs.

In the above embodiment, the lamp outer tube 2
At the time of replacement, air is usually mixed into the standing lamp until the standing lamp in the pipe shaft is connected to the new standing lamp after the old lamp tube is cut off from the standing tube 3a in the pipe shaft. In order to prevent this, a cap is fitted on the cut surface of the standpipe 3a.

At this time, if it takes time to cut the old lamp tube by cutting the old lamp tube, it takes time to cut the lamp tube, and if there is a relatively large amount of air mixed in from the cut surface of the standing tube 3a in the pipe shaft. If it is determined, in addition to the gas meter portion closest to the lamp tube (that is, the most upstream gas meter portion) of all the gas meters, the gas meter closest to the lamp tube on the upper floor (hereinafter referred to as the upstream gas meter) ) Section may be selected as another air purge point and an air purge may be performed. If there is a lot of air,
This is because the air may reach the upper floor.

Whether or not to perform the air purge on the upper floor is determined by, for example, the cutting time. If the cutting time is shorter than the predetermined first time, it is not necessary to perform the air purging on the upper floor, and the air purging is performed only in the most upstream gas meter portion. An air purge is performed in the upstream gas meter section in the upper floor section.

Further, when the cutting time is longer than the second time which is longer than the first time, it is determined that more air has been mixed in, and the air purging in the upstream gas meter portion in the further upper floor portion is performed. May be done. That is, it is determined whether or not to perform the air purge not only at the uppermost stream gas meter section but also at the upstream gas meter section on each floor according to the cutting time. Also on the upper floor, by performing the air purge in the upstream gas meter portion, the residual air in the gas pipe in the apartment house can be reduced and higher than in the case where the air purge is performed in the gas meter portion further downstream. Security can be ensured.

The scope of protection of the present invention is not limited to the above embodiments, but extends to the inventions described in the claims and their equivalents.

[0043]

As described above, according to the present invention, in the gas pipe replacement work for an apartment house, after the air purge is performed after the gas pipe replacement, the air purge point can ensure the safety without performing the ignition test for all the units. Is selected, construction efficiency and cost reduction are achieved. In addition, since it is not necessary to request the resident of the gas meter that performs the air purging to be at home on the day of construction, the burden on the resident can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram schematically illustrating a gas pipe replacement work method according to an embodiment of the present invention.

FIG. 2 is a diagram showing sampling positions in gas pipes in a building and their gas concentrations.

FIG. 3 is a processing flowchart of a gas pipe replacement construction method according to the embodiment of the present invention.

FIG. 4 is a diagram illustrating a conventional gas exchange construction method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main pipe 2 Lamp outer pipe 3a Standing pipe 3b Branch pipe M Gas meter

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ken Kawashima 1-5-20 Kaigan, Minato-ku, Tokyo Inside Tokyo Gas Co., Ltd. (72) Mikio Wakui 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd. (72) Inventor Noboru Miyamoto 1-5-20 Kaigan, Minato-ku, Tokyo Tokyo Gas Co., Ltd. F-term (reference) 2F030 CC13 CF13

Claims (4)

[Claims] 1. A gas pipe replacement work method for connecting a first gas pipe drawn into each of a plurality of dwelling units constituting an apartment house and replacing a second gas pipe extending outside the apartment house, The gas pipe is separated from the first gas pipe, and the old gas pipe is replaced with a new gas pipe, and among the plurality of gas meters for each dwelling unit connected to the first gas pipe, the gas pipe closest to the new gas pipe is used. A method of replacing a gas pipe, wherein an air purge for removing air from the new gas pipe is performed at a connection portion of the first gas meter with the first gas pipe. 2. The gas meter closest to the new gas pipe among the gas meters of dwelling units which are at home on the day of construction, wherein the gas meter closest to the new gas pipe is located on the day of construction. A method of replacing a gas pipe, wherein an air purge for removing air from the new gas pipe is performed at a connection portion with the gas pipe. 3. The gas meter according to claim 1, wherein when the apartment house has a plurality of first gas pipes, a plurality of gas meters connected to each first gas pipe are provided for each first gas pipe. Then, among the gas meters of the dwelling units at home on the day of the construction, an air purge for removing air in the new gas pipe is performed at a connection portion between the gas meter closest to the new gas pipe and the first gas pipe. A gas pipe replacement method characterized by the following. 4. The gas meter on the upper floor of the first gas meter according to any one of claims 1 to 3, wherein the time for disconnecting the second gas pipe from the first gas pipe is a predetermined time or more. A method of replacing a gas pipe, further comprising performing an air purge also at a connection portion of the second gas meter closest to the new gas pipe with the first gas pipe.