CN113720552A - Method for detecting leakage of commercial complex gas matching pipeline - Google Patents
Method for detecting leakage of commercial complex gas matching pipeline Download PDFInfo
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- CN113720552A CN113720552A CN202110928788.2A CN202110928788A CN113720552A CN 113720552 A CN113720552 A CN 113720552A CN 202110928788 A CN202110928788 A CN 202110928788A CN 113720552 A CN113720552 A CN 113720552A
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- 238000000034 method Methods 0.000 title claims abstract description 19
- 238000012360 testing method Methods 0.000 claims abstract description 30
- 239000007789 gas Substances 0.000 claims description 80
- 239000002737 fuel gas Substances 0.000 claims description 4
- 238000012423 maintenance Methods 0.000 claims description 4
- 238000001514 detection method Methods 0.000 abstract description 14
- 238000010586 diagram Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000013011 mating Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 230000007958 sleep Effects 0.000 description 1
- 238000013024 troubleshooting Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
- G01M3/28—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds
- G01M3/2807—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds for pipes
- G01M3/2815—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds for pipes using pressure measurements
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Abstract
The invention discloses a method for detecting leakage of a commercial complex gas matching pipeline, which is characterized in that the commercial complex is matched with the gas matching pipeline, the gas matching pipeline comprises a vertical pipe and a vertical pipe valve, the vertical pipe is provided with a pressure test valve and a connector, and the vertical pipe is provided with a plurality of branch pipes connected to gas-using equipment of different users and corresponding household valves; the external pressure gauge, the pressure test valve and the vertical pipe valve are matched to realize the pressure reduction and pressurization operation, so that whether the pipeline to be detected and the related valve, which are positioned in the rear end of the vertical pipe valve, of the vertical pipe valve and the gas matching pipeline leak gas or not during normal operation is detected and eliminated on the whole, and when no gas leaks in the whole detection, the detection is not needed one by one, the working efficiency is improved, the workload is reduced, and the trouble to users is avoided; when air leakage is confirmed on the whole, all users are checked, so that useless work can be effectively avoided.
Description
[ technical field ] A method for producing a semiconductor device
The invention relates to a method for detecting leakage of a commercial complex gas matching pipeline.
[ background of the invention ]
Commercial complex gas supporting pipeline, according to the regulation, must adorn the gas leakage warning in the client room, and client gas leakage can discover very easily, and pipeline and valve before introducing the client are external usually, and unable automated inspection reports to the police, need in addition regularly detect to and whether discovery exists gas leakage in time, and in time make a handle, guarantee safety. The number of users for the commercial complex is usually large, the current leak detection method is usually carried out by each user, the workload is very large, the time is consumed, and certain trouble is caused to the users. In reality, air leakage is accidental, air leakage is normally avoided in most cases, and whether air leakage exists, a large amount of work needs to be carried out every time detection is carried out, so that manpower and material resources are wasted.
The present invention has been made in view of the above circumstances.
[ summary of the invention ]
The invention aims to solve the technical problem of the prior art, provides a method for detecting leakage of a commercial complex gas matching pipeline, is simple and convenient to operate, can effectively detect whether the gas leaks or not, thereby quickly finishing work when no gas leaks, improving the working efficiency, reducing the workload, avoiding detection and troubleshooting of all users by doing useless work and avoiding causing troubles for use.
The invention is realized by the following technical scheme:
a method for detecting leakage of a commercial complex fuel gas matching pipeline comprises the following steps:
A. matching a commercial complex with a gas matching pipeline, wherein the gas matching pipeline comprises a vertical pipe which is pulled up from bottom to top on the commercial complex, the vertical pipe is provided with a vertical pipe valve, the vertical pipe is provided with a pressure test valve which is positioned behind the vertical pipe valve and close to the vertical pipe valve, the pressure test valve is provided with a connector which is externally connected with a pressure gauge, the vertical pipe is provided with a plurality of branch pipes which are connected with gas-using equipment of different users, and the branch pipes are provided with service valves;
B. setting the maintenance time, and informing a user to normally close the gas-using equipment in the period;
C. the pressure testing valve is in a closed state, the vertical pipe valve is in an open state, so that the gas matching pipeline is in a normal operation pressure state, the joint is connected with a pressure gauge, then the pressure testing valve is opened, and the pressure value in the normal operation pressure state is recorded;
D. the riser valve was closed and then the pressure change was observed through the pressure gauge:
in the first case: when the pressure is unstable and is reduced continuously, the gas in the gas matching pipeline is reduced, a vertical pipe valve needs to be opened, all users need to be checked, and hidden dangers are eliminated;
in the second case: when pressure stability does not constantly reduce, through the pressure testing valve gassing, with pressure reduction on normal operating pressure basis, observe the pressure variation through the manometer that connects pressure testing valve department:
1. when the pressure gradually rises and is close to or equal to the pressure value in the normal operation pressure state, the vertical pipe valve leaks air, the vertical pipe valve needs to be overhauled or replaced, when the vertical pipe valve has no problem, the vertical pipe valve is opened again to enable the pressure in the gas matching pipeline to reach the normal operation pressure, the vertical pipe valve is closed again, then the pressure change is observed through the pressure gauge, the observation time is longer than 10 minutes, and when the pressure of the pressure gauge is stable, the vertical pipe valve and the related valves do not leak air in the normal operation; if the pressure is unstable and drops, the vertical pipe valve is opened again, and all users are checked to eliminate hidden dangers;
2. when the pressure indicated by the pressure gauge does not rise, the vertical pipe valve does not leak gas, the pressure in a reduced state can be maintained, or the vertical pipe valve is opened again to enable the pressure of the gas matching pipeline to rise to a normal operation pressure state, then the vertical pipe valve is closed again, the pressure change is observed, the observation time is longer than 10 minutes, and if the pressure is stable, the pipeline to be detected and the related valve do not leak gas in normal operation; if the pressure is unstable and drops, the vertical pipe valve is opened again, and all users are checked to eliminate hidden dangers;
in the first and second cases, when all users need to be checked and hidden danger eliminated, after the hidden danger is eliminated, the vertical pipe valve is closed again when the gas supporting pipeline is in a normal operation pressure state, pressure change is observed, and when the pressure is stable, the gas supporting pipeline without hidden danger is free of air leakage in normal operation;
E. when the gas matching pipeline has no gas leakage, closing the vertical pipe valve, opening the pressure test valve, raising the pressure in the gas matching pipeline to 1.5 times of the normal operating pressure, testing, observing the pressure change condition, and detecting the reliability and stability of the gas matching pipeline;
F. and (5) recovering air supply.
The method for detecting the leakage of the commercial complex gas matching pipeline is characterized in that the maintenance time is designed in the later midnight.
In a method for leak detection of a commercial complex gas matching pipe as described above, the pressure is reduced by 1.5kpa in step E.
According to the method for detecting the leakage of the commercial complex gas matching pipeline, a three-way pipe is arranged between the pressure gauge and the joint, an exhaust valve is arranged at the third port of the three-way pipe, and gas in the gas matching pipeline is discharged through the exhaust valve so as to reduce the pressure.
Compared with the prior art, the invention has the following advantages: in practice, because the gas leakage is accidental in reality and the gas leakage is normal in most cases, in many leakage detection works, when the pipeline to be detected and the related valves, which are positioned in the rear ends of the vertical pipe valves and the gas matching pipelines, are detected to have no gas leakage in the normal operation process, the gas matching pipelines can be determined to have no gas leakage without detection by users, so that the working efficiency is improved, the workload is reduced, and the trouble to the users is avoided. When the possibility of air leakage of the pipeline to be detected and the related valve, which are positioned in the rear end of the vertical pipe valve, of the fuel gas matching pipeline is generally confirmed, all users are checked, and therefore useless work can be effectively avoided.
[ description of the drawings ]
The following detailed description of embodiments of the invention is provided in conjunction with the appended drawings, in which:
FIG. 1 is a schematic diagram of the structure of a gas mating line on a commercial complex.
[ detailed description ] embodiments
The invention is further described below with reference to the accompanying drawings:
a method for detecting leakage of a commercial complex fuel gas matching pipeline comprises the following steps:
A. as shown in fig. 1, a commercial complex is matched with a gas matching pipeline, the gas matching pipeline comprises a vertical pipe 1 which is pulled up from bottom to top on the commercial complex, a vertical pipe valve 2 is arranged on the vertical pipe 1, a pressure test valve 3 which is positioned behind the vertical pipe valve 2 and close to the vertical pipe valve 2 is arranged on the vertical pipe 1, a connector 5 which is externally connected with a pressure gauge 4 is arranged on the pressure test valve 3, a plurality of branch pipes 7 which are connected with gas appliances 6 of different users are arranged on the vertical pipe 1, and a service valve 8 is arranged on each branch pipe 7;
B. setting the maintenance time, and informing a user to normally close the gas-using equipment 6 in the period; preferably, the overhaul time is designed in the later midnight, and the time period after the user sleeps is utilized to avoid the time period when the user uses gas;
C. the pressure test valve 3 is in a closed state, the vertical pipe valve 2 is in an open state, so that the gas matching pipeline is in a normal operation pressure state, the pressure gauge 4 is connected to the joint 5, then the pressure test valve 3 is opened, and the pressure value in the normal operation pressure state is recorded;
D. the riser valve 2 is closed and then the pressure change is observed by the pressure gauge 4:
in the first case: when the pressure is unstable and is reduced continuously, the gas in the gas matching pipeline is reduced, the vertical pipe valve 2 needs to be opened, all users need to be checked, and hidden dangers are eliminated;
in the second case: when pressure stability does not constantly reduce, deflate through pressure testing valve 3, reduce pressure 1.5kpa on the basis of normal operating pressure, observe pressure variation through the manometer 4 that connects pressure testing valve 3 department:
1. when the pressure gradually rises and is close to or equal to the pressure value in the normal operation pressure state, the vertical pipe valve 2 leaks air, the vertical pipe valve 2 needs to be overhauled or replaced, when the vertical pipe valve 2 has no problem, the vertical pipe valve 2 is opened again to enable the pressure in the gas matching pipeline to reach the normal operation pressure, the vertical pipe valve 2 is closed again, then the pressure change is observed through the pressure gauge 4, the observation time is longer than 10 minutes, the selection time is 15 minutes, and when the pressure of the pressure gauge 4 is stable, the pipeline to be detected and the related valves do not leak air in the normal operation; then closing the vertical pipe valve 2, opening the pressure test valve 3, increasing the pressure in the gas matching pipeline to 1.5 times of the normal operation pressure for testing, observing the pressure change condition, and detecting the reliability and stability of the gas matching pipeline, wherein when the pressure change is small, the reliability and stability of the gas matching pipeline are normal; the leakage detection can be finished by recovering the gas supply;
if the pressure is unstable and drops, the vertical pipe valve 2 is opened again, and all users are checked to eliminate hidden dangers;
2. when the pressure shown by the pressure gauge 4 is not increased, the stand pipe valve 2 is not leaked, the pressure in a reduced state can be kept, or the stand pipe valve 2 is opened again to enable the pressure of the gas matching pipeline to be increased to a normal operation pressure state, then the stand pipe valve 2 is closed again, the pressure change is observed, the observation time is longer than 10 minutes, 15 minutes is selected, and if the pressure is stable, the pipeline to be detected and the related valve are not leaked in normal operation; then closing the vertical pipe valve 2, opening the pressure test valve 3, increasing the pressure in the gas matching pipeline to 1.5 times of the normal operation pressure for testing, observing the pressure change condition, and detecting the reliability and stability of the gas matching pipeline, wherein when the pressure change is small, the reliability and stability of the gas matching pipeline are normal; the leakage detection can be finished by recovering the gas supply;
if the pressure is unstable and drops, the vertical pipe valve 2 is opened again, and then all users are checked to eliminate hidden dangers;
in the first and second cases, when all users need to be checked and hidden dangers are eliminated, because the gas supporting pipeline is located outdoors of the users, the safety risk is low in a short time, the hidden dangers can be eliminated in the daytime, after the hidden dangers are eliminated, the vertical pipe valve 2 is closed again within a set overhauling time when the gas supporting pipeline is in a normal operation pressure state, the pressure change is observed, and when the pressure is stable, the gas supporting pipeline without hidden dangers does not leak in the normal operation; when the pipeline to be tested and related valves in the gas matching pipeline are not leaked, the vertical pipe valve 2 is closed, the pressure test valve 3 is opened, the pressure in the gas matching pipeline is increased to 1.5 times of the normal operation pressure for testing, the pressure change condition is observed, the reliability and stability of the gas matching pipeline are detected, and when the pressure change is small, the reliability and stability of the gas matching pipeline are normal; and the leakage detection can be finished by recovering the gas supply.
A three-way pipe is arranged between the pressure gauge 4 and the joint 5, an exhaust valve 9 is arranged on a third opening of the three-way pipe, gas in a gas matching pipeline is discharged through the exhaust valve 9 to reduce pressure, and repeated disassembly and assembly of the pressure gauge 4 in operation are avoided.
In reality, air leakage is accidental, and most of the air leakage is normal, so that in many leakage detection works, when the overall detection finds that the pipeline to be detected, in which the vertical pipe valve 2 and the gas matching pipeline are located at the rear end of the vertical pipe valve 2, and the related valves do not have air leakage in normal operation, the fact that the gas matching pipeline has no air leakage can be determined, detection is not needed to be carried out on a user-by-user basis, the working efficiency is improved, the workload is reduced, and troubles to the user are avoided. When the possibility of air leakage of the pipeline to be detected and the related valves of the gas matching pipeline positioned in the rear end of the vertical pipe valve 2 is confirmed on the whole, all users are checked, and therefore useless work can be effectively avoided.
Claims (4)
1. A method for detecting leakage of a commercial complex fuel gas matching pipeline is characterized by comprising the following steps:
A. the method comprises the following steps that a commercial complex is matched with a gas matching pipeline, the gas matching pipeline comprises a vertical pipe (1) which is pulled up from bottom to top on the commercial complex, a vertical pipe valve (2) is arranged on the vertical pipe (1), a pressure test valve (3) which is positioned behind the vertical pipe valve (2) and close to the vertical pipe valve (2) is arranged on the vertical pipe (1), a connector (5) which is externally connected with a pressure gauge (4) is arranged on the pressure test valve (3), a plurality of branch pipes (7) which are connected with gas-using equipment (6) of different users are arranged on the vertical pipe (1), and household valves (8) are arranged on the branch pipes (7);
B. setting the maintenance time, and informing a user to normally close the gas-using equipment (6) in the period;
C. the pressure testing valve (3) is in a closed state, the vertical pipe valve (2) is in an open state, so that the gas supporting pipeline is in a normal operation pressure state, the pressure gauge (4) is connected to the joint (5), then the pressure testing valve (3) is opened, and the pressure value in the normal operation pressure state is recorded;
D. closing the vertical pipe valve (2), and observing pressure change through a pressure gauge (4):
in the first case: when the pressure is unstable and is reduced continuously, the gas in the gas matching pipeline is reduced, the vertical pipe valve (2) needs to be opened, all users need to be checked, and hidden dangers are eliminated;
in the second case: when pressure stability does not constantly reduce, through pressure testing valve (3) gassing, with pressure reduction on normal operating pressure basis, observe pressure variation through manometer (4) of connecing pressure testing valve (3) department:
1. when the pressure gradually rises and is close to or equal to the pressure value in the normal operation pressure state, the vertical pipe valve (2) leaks air, the vertical pipe valve (2) needs to be overhauled or replaced, when the vertical pipe valve (2) has no problem, the vertical pipe valve (2) is reopened to enable the pressure in the gas matching pipeline to reach the normal operation pressure, the vertical pipe valve (2) is reopened, then the pressure change is observed through the pressure gauge (4), the observation time is longer than 10 minutes, and when the pressure of the pressure gauge (4) is stable, the pipeline to be measured and the related valves do not leak air in the normal operation; if the pressure is unstable and drops, the vertical pipe valve (2) is opened again, and all users are checked to eliminate hidden dangers;
2. when the pressure of the pressure gauge (4) is not increased, the vertical pipe valve (2) is not leaked, the pressure in a reduced state can be kept, or the vertical pipe valve (2) is opened again to enable the pressure of the gas matching pipeline to be increased to a normal operation pressure state and then the vertical pipe valve (2) is closed again, the pressure change is observed, the observation time is longer than 10 minutes, and if the pressure is stable, the pipeline to be detected and the related valve are not leaked in normal operation; if the pressure is unstable and drops, the vertical pipe valve (2) is opened again, and all users are checked to eliminate hidden dangers;
in the first and second cases, when all users need to be checked and hidden danger eliminated, after the hidden danger is eliminated, the vertical pipe valve (2) is closed again when the gas supporting pipeline is in a normal operation pressure state, pressure change is observed, and when the pressure is stable, the gas supporting pipeline without hidden danger is free of air leakage in normal operation;
E. when the gas matching pipeline is not leaked, the vertical pipe valve (2) is closed, the pressure test valve (3) is opened, the pressure in the gas matching pipeline is increased to 1.5 times of the normal operation pressure for testing, the pressure change condition is observed, and the reliability and the stability of the gas matching pipeline are detected;
F. and (5) recovering air supply.
2. The method of claim 1, wherein the method comprises the steps of: the service time is designed in the late night.
3. The method of claim 1, wherein the method comprises the steps of: in step E the pressure was reduced by 1.5 kpa.
4. The method of claim 1, wherein the method comprises the steps of: a three-way pipe is arranged between the pressure gauge (4) and the joint (5), an exhaust valve (9) is arranged on a third opening of the three-way pipe, and gas in the gas matching pipeline is discharged through the exhaust valve (9) to reduce pressure.
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114484294A (en) * | 2021-12-29 | 2022-05-13 | 东本电气科技(苏州)有限公司 | Gas riser leak detection method and leak detection device |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000131183A (en) * | 1998-10-26 | 2000-05-12 | Ito Koki Kk | Method and device for gas conduit leakage detection |
CN103674447A (en) * | 2012-08-31 | 2014-03-26 | 宝山钢铁股份有限公司 | Online valve leakage testing device and method for combustible gas pipeline |
CN105651472A (en) * | 2016-04-11 | 2016-06-08 | 重庆燃气集团股份有限公司 | Device integrating fuel gas plugging and vertical pipe pressure testing and plugging pressure testing method |
CN210037111U (en) * | 2019-07-09 | 2020-02-07 | 润智科技有限公司 | Gas pipeline sealing performance detection device |
CN212568267U (en) * | 2020-05-06 | 2021-02-19 | 大连旅顺港华燃气有限公司 | Gas pipeline pressure test and quick leak detection device |
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2021
- 2021-08-13 CN CN202110928788.2A patent/CN113720552A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000131183A (en) * | 1998-10-26 | 2000-05-12 | Ito Koki Kk | Method and device for gas conduit leakage detection |
CN103674447A (en) * | 2012-08-31 | 2014-03-26 | 宝山钢铁股份有限公司 | Online valve leakage testing device and method for combustible gas pipeline |
CN105651472A (en) * | 2016-04-11 | 2016-06-08 | 重庆燃气集团股份有限公司 | Device integrating fuel gas plugging and vertical pipe pressure testing and plugging pressure testing method |
CN210037111U (en) * | 2019-07-09 | 2020-02-07 | 润智科技有限公司 | Gas pipeline sealing performance detection device |
CN212568267U (en) * | 2020-05-06 | 2021-02-19 | 大连旅顺港华燃气有限公司 | Gas pipeline pressure test and quick leak detection device |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN114484294A (en) * | 2021-12-29 | 2022-05-13 | 东本电气科技(苏州)有限公司 | Gas riser leak detection method and leak detection device |
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