WO2014139945A1 - Method for selective pin-pointing of utility gas leaks - Google Patents

Method for selective pin-pointing of utility gas leaks Download PDF

Info

Publication number
WO2014139945A1
WO2014139945A1 PCT/EP2014/054572 EP2014054572W WO2014139945A1 WO 2014139945 A1 WO2014139945 A1 WO 2014139945A1 EP 2014054572 W EP2014054572 W EP 2014054572W WO 2014139945 A1 WO2014139945 A1 WO 2014139945A1
Authority
WO
WIPO (PCT)
Prior art keywords
gas
tracer
pipe
utility
leak
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/EP2014/054572
Other languages
French (fr)
Inventor
Fredrik Enquist
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Inficon GmbH Deutschland
Original Assignee
Inficon GmbH Deutschland
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Inficon GmbH Deutschland filed Critical Inficon GmbH Deutschland
Priority to US14/772,651 priority Critical patent/US20160109320A1/en
Priority to JP2015562069A priority patent/JP2016510117A/en
Priority to CN201480011885.3A priority patent/CN105074412A/en
Priority to RU2015142870A priority patent/RU2015142870A/en
Publication of WO2014139945A1 publication Critical patent/WO2014139945A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • 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
    • G01M3/04—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point
    • G01M3/20—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using special tracer materials, e.g. dye, fluorescent material, radioactive material
    • G01M3/22—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using special tracer materials, e.g. dye, fluorescent material, radioactive material for pipes, cables or tubes; for pipe joints or seals; for valves; for welds; for containers, e.g. radiators
    • 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
    • G01M3/04—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point
    • G01M3/20—Investigating fluid-tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using special tracer materials, e.g. dye, fluorescent material, radioactive material

Definitions

  • the present invention relates to a method for precise pin-pointing of leaks in underground gas pipes in accordance with the preamble of claim 1.
  • Probe holes are drilled through the hard cover at 1 to 2 m distance in the area where the gas leak was detected. The holes are drilled right above and along the route of the presumably leaking pipe.
  • the holes are left to ventilate for a while.
  • a detector "sniffer” is placed in the holes and measures the gas concentration pumped out of the hole by the detector.
  • the process of drilling holes requires special equipment such as a drilling machine and a power source for the drill.
  • the power source is typically either a compressed air unit or an electric power generator. In either case it adds to the complexity of the whole operation.
  • the current method is time consuming and not as accurate as desired.
  • the main reason for the limited accuracy is that the leak is typically rather old meaning the gas has had time to spread quite a bit sideways.
  • gas is detected in an area stretching 5 to 20 meters along the route of the pipe. Considerable larger areas are often encountered and it is also common that gas is detected not directly above the pipe but instead beside the pipe at the edge of the road or sidewalk or along the curb. This also means that it is quite common to find more than one gas area from one leak.
  • Typical accuracy using the probe hole procedure is +/- 2 m but it is common that two or more holes show peak concentrations forcing the crew to dig in the wrong place or to dig more than would be necessary if more accurate pin-pointing was possible.
  • the two most advantageous tracer gases to use are hydrogen and helium. There are selective detectors for both these gases. The addition of helium would reduce the energy content of the gas and hence affect the efficiency of the appliances using the gas.
  • the method according to the present invention requires the use of a highly selective detector that will react much stronger to the added tracer gas than to the gas originally in the pipe.
  • the selectivity factor should preferably be several orders of magnitude for optimal employment of this method. Detectors with this quality are manufactured and sold by INFICON AB in Sweden. The selectivity of this detector for hydrogen as compared to methane is more than 5 orders of magnitude.
  • the method further requires access to suitable injection points which are possible points for connecting and injecting the tracer gas into the pipe.
  • Fig. 2 shows the tracer gas concentration at the surface
  • Fig. 3 shows the arrangement of Fig. 1 by use of mere utility gas without tracer gas
  • Fig. 4 shows the utility gas concentration profile at the surface
  • Fig. 5 shows the arrangement according to Fig. 1 by use of a utility gas and the tracer gas of the invention
  • Fig. 6 shows the gas concentrations at the surface.
  • Fig. 1 shows a gas pipe 12 below the surface 14 of the ground 16.
  • the pipe 12 is thus entirely surrounded by ground material 16.
  • the pipe 12 is positioned below the ground surface 14.
  • the pipe 12 carries the tracer gas 18 in the direction of arrow 20 in Fig. 1.
  • the pipe 12 contains a tracer gas 18 only and no utility gas 26.
  • the tracer gas 18 enters the pipe 12 upstream of the leak 22 and exits the pipe 12.
  • Fig. 1 shows how the tracer gas 18 spreads out of the leak 22 and within the ground 16.
  • a fairly narrow plume 24 of tracer gas 18 forms within the soil.
  • the plume 24 is very narrow at the leak position 22 and expands until it reaches a surface 14.
  • Fig. 2 shows the tracer gas concentration at the surface 14. It can be realized that the diameter of the tracer gas concentration at the surface 14 is about one meter. This is typical in the case of hydrogen and helium. The diameter of the tracer gas plume 24 at the surface 14 will increase over time. Therefore, it is desirable to perform the leak detection or pin-pointing shortly after introduction of the tracer gas 18 to the pipe 12.
  • Fig. 3 shows the case where the pipe 12 only carries a utility gas 26 but no tracer gas 18.
  • the gas is carried in the direction of arrow 20 in Fig. 3. This is not an embodiment of the invention, but rather shown for illustration purposes.
  • the utility gas 26 will exit the pipe 12 at the position of the leak 22 and it will expand throughout the surrounding ground material 16 in an area which is much wider than the area of the tracer gas plume 24 in Fig. 1.
  • Fig. 4 shows an example of the concentration profile of the utility gas 26 at the surface 14 which will form according to Fig. 3.
  • the leaking utility gas 26 will form a cloud within the ground 16 and reach an outer diameter typically in the range between 5 and 25 meters at the surface 14. It can be immediately realized that it will be very hard and imprecise to detect the position of the leak 22 only from measuring the gas 18 at the surface 14.
  • Fig. 5 now shows the embodiment of the invention where the pipe 12 carries a utility gas 26, such as methane and a tracer gas 18 such as hydrogen or helium.
  • Fig. 5 shows that both the utility gas 26 and the tracer gas 18 escape from the leak 22 into the ground 16.
  • the ground 16 is saturated with a large volume of utility gas 26 which expands within a very large area of the ground surface 14, as explained above with regard to Figs. 3 and 4.
  • the hydrogen or helium tracer gas 18 is much lighter than air and therefore ascends within the ground 16 from the leak 22 up to the surface 14 without expanding as much as the utility gas 26.
  • the tracer gas 18 is detected with a sniffing probe 28 above the surface 14.
  • the sniffing probe 28 is at least ten times more sensitive to the tracer gas 28 than to the utility gas 26.
  • Fig. 6 shows the concentration profile on the surface 14 of the utility gas 26 and of the tracer gas 18.
  • the gas detector 28 When using the gas detector 28 according to the method of the invention which is much more sensitive to the tracer gas 18 than to the utility gas 26, the gas detector 28 will selectively detect the tracer gas 18 within its much more narrow expansion area 30 at the surface 14 compared to the expansion area 29 of the utility gas 26. Consequently, the possible area of the leak 22 of the gas pipe 12 is considerably smaller when using the method of the invention compared to leak detection methods which require detecting the utility gas 26 at the ground surface 14.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Examining Or Testing Airtightness (AREA)
  • Medical Treatment And Welfare Office Work (AREA)

Abstract

A method for detecting the location of a gas leak (22) in buried utility gas pipes (12) by measuring the presence of a gas (18) below or above the ground surface (14) above the pipe (12) is improved by injecting a tracer gas (18) which is lighter than air into the utility gas (26) within the pipe (12) and by using a gas detector (28) having a higher sensitivity to the tracer gas (18) than to the utility gas (26) for pin-pointing the leak position (22).

Description

Method for selective pin-pointing of utility gas leaks
Field of the invention
The present invention relates to a method for precise pin-pointing of leaks in underground gas pipes in accordance with the preamble of claim 1.
Background of the invention
Regulations throughout the world require regular survey of gas networks to check for unknown leakage. The reason for this is primarily to protect the public from fires and explosions resulting from gas collecting in buildings and other confined spaces. The leak survey is typically carried out by moving a detector, sensitive to one of the main components of the gas, over the surface of the ground above the pipe carrying the gas. If leakage is detected in an underground gas line, the location of the leak must be pin-pointed to reduce the excavation work to a minimum. This has long posed difficult problems for repair crews. Although the gas line itself is often located, the soil is often saturated with gas, which makes it difficult to pin-point the actual location of the leak. As a result, it is not uncommon for large stretches of a surface, including paved roadways, to require excavation to precisely locate the leak - a situation that can be costly, time consuming, and potentially hazardous.
The most common pin-pointing procedure on hard coated surfaces is roughly the following :
Probe holes are drilled through the hard cover at 1 to 2 m distance in the area where the gas leak was detected. The holes are drilled right above and along the route of the presumably leaking pipe.
The holes are left to ventilate for a while. A detector "sniffer" is placed in the holes and measures the gas concentration pumped out of the hole by the detector.
Further and more closely spaced holes are drilled around the hole or holes showing the highest concentration until the crew feel that accuracy is satisfactory or that better accuracy cannot be achieved.
There are two reasons for making the holes:
Reducing the influence of ground and surface conditions on the position of the highest concentration making it appear somewhere else than right above the actual leak, and to allow venting out the gas from the soil so that the gas concentration profile is in a steady state and thereby improving precision of pin-pointing. To achieve a steady state situation it is vital that the holes are going most or all of the way down to the leaking pipe. It is also important that the holes are big enough to allow proper ventilation of the accumulated gas.
The process of drilling holes requires special equipment such as a drilling machine and a power source for the drill. The power source is typically either a compressed air unit or an electric power generator. In either case it adds to the complexity of the whole operation.
In addition to the time and effort spent there are also two serious risks involved :
When drilling a whole there is a risk that a large amount of gas is released that could be ignited by sparks formed when drilling or by some other ignition source, and the pipe may be damaged from the drilling which can cause substantial leakage with associated fire and explosion risks.
The current method is time consuming and not as accurate as desired. The main reason for the limited accuracy is that the leak is typically rather old meaning the gas has had time to spread quite a bit sideways. Typically gas is detected in an area stretching 5 to 20 meters along the route of the pipe. Considerable larger areas are often encountered and it is also common that gas is detected not directly above the pipe but instead beside the pipe at the edge of the road or sidewalk or along the curb. This also means that it is quite common to find more than one gas area from one leak.
Typical accuracy using the probe hole procedure is +/- 2 m but it is common that two or more holes show peak concentrations forcing the crew to dig in the wrong place or to dig more than would be necessary if more accurate pin-pointing was possible. Summary of the invention
It is an object of the present invention to provide an improved method for pinpointing leaks in buried gas pipes by injecting a tracer gas in the pipe shortly before performing the pin-pointing operation.
This is achieved in accordance with the characterizing portion of claim 1.
By injecting a lighter than air tracer gas, for which there is a selective and sensitive detector, into the leaking pipe pin-pointing the leak will become much more accurate and considerably easier to perform as the gas will not have time to spread widely in the ground before the pin-pointing work begins.
This is achieved by following phenomena :
The spread of the added gas is minimal as it started leaking just recently (hours before pin-pointing) . Hydrogen readily rises to the surface and penetrates most surface layers without the need for drilling probe holes.
The two most advantageous tracer gases to use are hydrogen and helium. There are selective detectors for both these gases. The addition of helium would reduce the energy content of the gas and hence affect the efficiency of the appliances using the gas.
By choosing hydrogen the influence on the gas will be minimal and there are suitable selective detectors on the market.
The method according to the present invention requires the use of a highly selective detector that will react much stronger to the added tracer gas than to the gas originally in the pipe. The selectivity factor should preferably be several orders of magnitude for optimal employment of this method. Detectors with this quality are manufactured and sold by INFICON AB in Sweden. The selectivity of this detector for hydrogen as compared to methane is more than 5 orders of magnitude.
Furthermore, the need for drilling probe holes will be greatly reduced when employing the present invention.
The method further requires access to suitable injection points which are possible points for connecting and injecting the tracer gas into the pipe.
An embodiment of the invention is described with reference to the drawings. shows the arrangement for performing the method of the invention under use of mere tracer
Fig. 2 shows the tracer gas concentration at the surface,
Fig. 3 shows the arrangement of Fig. 1 by use of mere utility gas without tracer gas,
Fig. 4 shows the utility gas concentration profile at the surface,
Fig. 5 shows the arrangement according to Fig. 1 by use of a utility gas and the tracer gas of the invention and
Fig. 6 shows the gas concentrations at the surface.
Fig. 1 shows a gas pipe 12 below the surface 14 of the ground 16. The pipe 12 is thus entirely surrounded by ground material 16. The pipe 12 is positioned below the ground surface 14. The pipe 12 carries the tracer gas 18 in the direction of arrow 20 in Fig. 1. The pipe 12 contains a tracer gas 18 only and no utility gas 26. The tracer gas 18 enters the pipe 12 upstream of the leak 22 and exits the pipe 12.
Fig. 1 shows how the tracer gas 18 spreads out of the leak 22 and within the ground 16. A fairly narrow plume 24 of tracer gas 18 forms within the soil. The plume 24 is very narrow at the leak position 22 and expands until it reaches a surface 14.
Fig. 2 shows the tracer gas concentration at the surface 14. It can be realized that the diameter of the tracer gas concentration at the surface 14 is about one meter. This is typical in the case of hydrogen and helium. The diameter of the tracer gas plume 24 at the surface 14 will increase over time. Therefore, it is desirable to perform the leak detection or pin-pointing shortly after introduction of the tracer gas 18 to the pipe 12.
Fig. 3 shows the case where the pipe 12 only carries a utility gas 26 but no tracer gas 18. The gas is carried in the direction of arrow 20 in Fig. 3. This is not an embodiment of the invention, but rather shown for illustration purposes. The utility gas 26 will exit the pipe 12 at the position of the leak 22 and it will expand throughout the surrounding ground material 16 in an area which is much wider than the area of the tracer gas plume 24 in Fig. 1.
Fig. 4 shows an example of the concentration profile of the utility gas 26 at the surface 14 which will form according to Fig. 3. The leaking utility gas 26 will form a cloud within the ground 16 and reach an outer diameter typically in the range between 5 and 25 meters at the surface 14. It can be immediately realized that it will be very hard and imprecise to detect the position of the leak 22 only from measuring the gas 18 at the surface 14. Fig. 5 now shows the embodiment of the invention where the pipe 12 carries a utility gas 26, such as methane and a tracer gas 18 such as hydrogen or helium. Fig. 5 shows that both the utility gas 26 and the tracer gas 18 escape from the leak 22 into the ground 16. The ground 16 is saturated with a large volume of utility gas 26 which expands within a very large area of the ground surface 14, as explained above with regard to Figs. 3 and 4.
The hydrogen or helium tracer gas 18, however, is much lighter than air and therefore ascends within the ground 16 from the leak 22 up to the surface 14 without expanding as much as the utility gas 26. The tracer gas 18 is detected with a sniffing probe 28 above the surface 14. The sniffing probe 28 is at least ten times more sensitive to the tracer gas 28 than to the utility gas 26.
Fig. 6 shows the concentration profile on the surface 14 of the utility gas 26 and of the tracer gas 18.
When using the gas detector 28 according to the method of the invention which is much more sensitive to the tracer gas 18 than to the utility gas 26, the gas detector 28 will selectively detect the tracer gas 18 within its much more narrow expansion area 30 at the surface 14 compared to the expansion area 29 of the utility gas 26. Consequently, the possible area of the leak 22 of the gas pipe 12 is considerably smaller when using the method of the invention compared to leak detection methods which require detecting the utility gas 26 at the ground surface 14.

Claims

Claims
1. Method for detecting the location of a gas leak (22) in buried utility gas pipes (12) by measuring the presence of a gas (18) below or above the ground surface (14) above the pipe (12), c h a r a c t e r i z e d i n t h a t a tracer gas (18) which is lighter than air is injected into the utility gas (26) within the pipe (12), and a gas detector (28) having a higher sensitivity to the tracer gas (18) than to the utility gas (26) is used to pin-point the leak position (22).
2. Method according to claim 1, wherein the tracer gas (18) is hydrogen.
3. The method according to claim 1, wherein the tracer gas (18) is helium.
4. The method according to anyone of claims 1-3, wherein the gas detector (28) is at least ten times more sensitive to the tracer gas (18) than to the utility gas (26) .
5. The method according to anyone of the preceding claims, wherein the gas detector (28) is at least a hundred times more sensitive to the tracer gas ( 18) than to the utility gas (26).
6. The method according to anyone of the preceding claims, wherein the gas detector (28) is at least a thousand times more sensitive to the tracer gas (18) than to the utility gas (26) .
7. The method according to anyone of the preceding claims, wherein the tracer gas ( 18) is at least ten thousand times more sensitive to the tracer gas (18) than to the utility gas (26) .
8. The method according to anyone of the preceding claims, wherein the tracer gas ( 18) is injected into the gas pipe (12) upstream of the assumed leak (22).
9. The method according to anyone of the preceding claims, wherein the tracer gas (18) is injected into the gas pipe (12) such that the pressure within the gas pipe ( 12) is higher than atmosphere.
10. The method according to anyone of the preceding claims, wherein the tracer gas (18) is injected no longer than 48 hours before performing the leak detection.
11. The method according to anyone of the preceding claims, wherein the tracer gas (18) is injected into the pipe (12) no longer than 18 hours and, preferably, no longer than 12 hours before performing the leak detection.
12. The method according to anyone of the proceeding claims, wherein the tracer gas (18) is injected into the pipe (12) at least 30 minutes and no longer than 8 hours before performing the leak detection.
PCT/EP2014/054572 2013-03-11 2014-03-10 Method for selective pin-pointing of utility gas leaks Ceased WO2014139945A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
US14/772,651 US20160109320A1 (en) 2013-03-11 2014-03-10 Method for selective pin-pointing of utility gas leaks
JP2015562069A JP2016510117A (en) 2013-03-11 2014-03-10 How to selectively locate utility gas leaks
CN201480011885.3A CN105074412A (en) 2013-03-11 2014-03-10 Method for Selectively Indicating Gas Leakage
RU2015142870A RU2015142870A (en) 2013-03-11 2014-03-10 METHOD FOR SELECTIVE PRECISE DETERMINATION OF LOCAL GAS LEAKS

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP13158654.7A EP2778644A1 (en) 2013-03-11 2013-03-11 Method for selective pin-pointing of utility gas leaks
EP13158654.7 2013-03-11

Publications (1)

Publication Number Publication Date
WO2014139945A1 true WO2014139945A1 (en) 2014-09-18

Family

ID=47900725

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2014/054572 Ceased WO2014139945A1 (en) 2013-03-11 2014-03-10 Method for selective pin-pointing of utility gas leaks

Country Status (6)

Country Link
US (1) US20160109320A1 (en)
EP (1) EP2778644A1 (en)
JP (1) JP2016510117A (en)
CN (1) CN105074412A (en)
RU (1) RU2015142870A (en)
WO (1) WO2014139945A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107271110A (en) * 2017-07-12 2017-10-20 北京市燃气集团有限责任公司 A kind of steel gas pipe underground leak point positioning detection method positioned based on the Big Dipper

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108506739A (en) * 2018-04-25 2018-09-07 邳州中燃城市燃气发展有限公司 A kind of town gas pipe leakage detecting and locating method
CN113135381A (en) * 2020-01-18 2021-07-20 天津大港油田圣达科技有限公司 Technology for determining gas storage tightness by tracer

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4127543A1 (en) * 1991-08-20 1993-02-25 Werner Ratfisch Trolley mounted gas leak detection unit for monitoring gas pipelines - in which analyser is built into housing having at least 2 rollers and suction pump draws in gases via funnel inlet and supplies them to analyser
US6067844A (en) * 1997-08-15 2000-05-30 Shell Oil Company Nondestructive method for detection of defects and the condition of liners in polymer-lined pipes and equipment
US20100288020A1 (en) * 2007-10-15 2010-11-18 Adixen Scandinavia Ab Leak detection system comprising a tracer gas mediating unit
WO2011124613A1 (en) * 2010-04-09 2011-10-13 Inficon Gmbh A leak detector with optical tracer gas detection

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2511759A1 (en) * 1975-03-18 1976-10-07 Leybold Heraeus Gmbh & Co Kg VACUUM LEAK DETECTION METHODS ON EXTENDED SYSTEMS
IT1122256B (en) * 1979-07-23 1986-04-23 Varian Spa METHOD FOR LOCATING ONE OR MORE LOSSES IN UNDERGROUND TUBES
EP0365042A1 (en) * 1987-03-31 1990-04-25 FINN-AQUA SANTASALO-SOHLBERG GmbH Method for monitoring leakage in liquid conduit systems of cold drying equipment and adapted cold drying equipment for carrying out this method
US4972704A (en) * 1989-03-14 1990-11-27 Shell Oil Company Method for troubleshooting gas-lift wells
JPH09159564A (en) * 1995-12-07 1997-06-20 Tokyo Gas Co Ltd Gas leak detection method and apparatus used therefor
DE19819029A1 (en) * 1998-04-29 1999-11-04 Linde Ag Procedure for leak detection on gas pipes
WO2004113862A1 (en) * 2003-06-11 2004-12-29 Varian, Inc. Methods and apparatus for leak detection in contaminated environments
US7331248B2 (en) * 2003-10-06 2008-02-19 Vista Engineering Technologies, Inc. Method and apparatus for detecting and locating explosives, biological, and chemical substances in ducts and structures using tracers
JP4372637B2 (en) * 2004-08-03 2009-11-25 トヨタ自動車株式会社 Gas leak detection mechanism
JP4281001B2 (en) * 2004-09-15 2009-06-17 独立行政法人産業技術総合研究所 Gas leak inspection device
CN1936413A (en) * 2006-09-29 2007-03-28 淄博思科光电科技有限公司 Underground pipeline leak-detection method and apparatus
JP2009300198A (en) * 2008-06-12 2009-12-24 Tokyo Gas Co Ltd Detecting method of leak of fuel gas
US8692186B2 (en) * 2010-08-10 2014-04-08 Wilco Ag Method and apparatus for leak testing containers
CN102086972A (en) * 2010-11-17 2011-06-08 广州精测管线技术有限公司 Method for detecting leaking point position of buried pipeline by gas

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4127543A1 (en) * 1991-08-20 1993-02-25 Werner Ratfisch Trolley mounted gas leak detection unit for monitoring gas pipelines - in which analyser is built into housing having at least 2 rollers and suction pump draws in gases via funnel inlet and supplies them to analyser
US6067844A (en) * 1997-08-15 2000-05-30 Shell Oil Company Nondestructive method for detection of defects and the condition of liners in polymer-lined pipes and equipment
US20100288020A1 (en) * 2007-10-15 2010-11-18 Adixen Scandinavia Ab Leak detection system comprising a tracer gas mediating unit
WO2011124613A1 (en) * 2010-04-09 2011-10-13 Inficon Gmbh A leak detector with optical tracer gas detection

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107271110A (en) * 2017-07-12 2017-10-20 北京市燃气集团有限责任公司 A kind of steel gas pipe underground leak point positioning detection method positioned based on the Big Dipper

Also Published As

Publication number Publication date
CN105074412A (en) 2015-11-18
US20160109320A1 (en) 2016-04-21
RU2015142870A (en) 2017-04-17
JP2016510117A (en) 2016-04-04
EP2778644A1 (en) 2014-09-17

Similar Documents

Publication Publication Date Title
CN107271110B (en) A kind of steel gas pipe underground leak point positioning detection method based on Big Dipper positioning
Forde et al. Identification, spatial extent and distribution of fugitive gas migration on the well pad scale
EP2831557B1 (en) Leak location detection system
Zipf Jr et al. Deflagration-to-detonation transition in natural gas–air mixtures
CN102086972A (en) Method for detecting leaking point position of buried pipeline by gas
EP2778644A1 (en) Method for selective pin-pointing of utility gas leaks
Cao et al. Prevention and control of coalfield fire technology: A case study in the Antaibao Open Pit Mine goaf burning area, China
CN108316929A (en) A kind of water conservancy and hydropower gas Tunnel Construction
CN108119759A (en) A kind of underground gas pipeline leakage point accurate positioning method and system
Maazallahi et al. Intercomparison of detection and quantification methods for methane emissions from the natural gas distribution network in Hamburg, Germany
Kim Locating fires in abandoned underground coal mines
EP2993456A1 (en) Method for selective pin-pointing of utility gas leaks during operation
US7210336B1 (en) Gas link leak evacuation and monitoring system
Justin et al. Mine fire diagnostics to locate and monitor abandoned mine fires
CN115978467B (en) Underground gas pipeline leakage point positioning method and system based on negative pressure driving
CN110794478B (en) A comprehensive detection method for harmful gases in non-coal-measure strata tunnels
Ghafurian et al. Leak location in fluid filled cables using the PFT method
US20070051511A1 (en) System and method for breach detection in petroleum wells
CN116183123B (en) Detection method for leakage points and external contaminated areas in the anti-seepage system of an operational solid waste landfill
Heiser et al. Using perfluorocarbon tracers for verification of cap and cover systems performance.
Jones et al. Continuous monitoring of natural CO2 emissions near Rome–lessons for low-level CO2 leakage detection
Rao et al. Verification of a Mobile Artificial Testbed (MAT) for Belowground Natural Gas Pipeline Leaks
CN120368226A (en) A method for detecting water leakage in pipeline
Szollosi-Moţa et al. MIGRATION OF NATURAL GAS RELEASED FROM DAMAGED DISTRIBUTION PIPELINES THROUGH SOIL.
Lee et al. Case Study on Gas Emission and induced Explosion during Tunnelling in Taiwan

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 201480011885.3

Country of ref document: CN

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 14709256

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 14772651

Country of ref document: US

ENP Entry into the national phase

Ref document number: 2015562069

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 2015142870

Country of ref document: RU

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 14709256

Country of ref document: EP

Kind code of ref document: A1