LEAK DETECTION FORMULA, ANALYZER and METHODS OF USE

• US 20140251831A1
• Filed: 03/07/2013
• Published: 09/11/2014
• Est. Priority Date: 03/07/2013
• Status: Active Grant

• Current Assignee: Automotive Test Solutions, Inc.
• Original Assignee: Automotive Test Solutions, Inc.
• Inventors: Pederson, Neal R., Thoma, Steven G., Thompson, Bernie C., Ley, Kenneth D.
• Granted Patent: US 10,222,291 B2
• Time in Patent Office: Days
• US Class Current: 205/780.5
• CPC Class Codes: G01M 3/042 by using materials which expand, contract, disintegrate, or decompose in contact with a fluid G01M3/12 takes precedence
• CPC Class Codes: G01M 3/226 for containers, e.g. radiators

Abstract

Detecting a leak from a site in a sealed system with a source of pressurized gas which is capable of passing through the site, a composition of matter which adheres to the surfaces of the system and which is capable of showing the presence of the gas escaping from the site. The method includes: injecting gas into the system to a pressure in excess of the surrounding pressure, and covering the external surface with the composition to identify the location of the site by the interaction of the escaping gas with the composition. The composition is foam that includes a surfactant which forms a least one bubble in the presence of escaping gas and an indicator which changes color in the presence of the escaping gas. The leak is an opening down to at least the size of a hole 0.001″ in diameter. A gas detector may also be used.

Claims

1. A method of detecting a leak from a leak site in a sealed system, the sealed system including one or more external surfaces, the method including the use of a source of pressurized gas external to the sealed system which gas is capable of passing through the leak site and a composition of matter which is capable of adhering to at least a portion of the one or more external surfaces and which is capable of showing the presence of the gas escaping from the leak site, the method including the steps of:

injecting gas from the external source into the sealed system to a pressure in excess of the pressure surrounding the sealed system; and

covering at least a portion of the external surface with the composition of matter to identify the location of the leak site by the interaction of the gas escaping from the leak site with the composition of matter.

2. The method as set forth in claim 1, wherein the composition of matter includes at least one surfactant capable of forming a least one bubble in the presence of gas escaping from the leak site, and the step of covering includes covering the area of the leak site.

3. The method as set forth in claim 2, wherein the composition of matter is a solution, and the step of covering includes covering the area of the leak site so that the interaction of the solution and the gas will form the at least one bubble.

4. The method as set forth in claim 2, wherein the composition of matter is a foam, and the step of covering includes covering the area of the leak site so that the interaction of the solution and the gas will form the at least one bubble.

5. The method as set forth in claim 1, wherein the composition of matter has a first color that changes to a second color in the presence of the gas escaping from the leak site, and wherein the method further includes the step examining the composition of matter after it has been applied to at least a portion of the external surface to locate the leak site by the presence of the second color around the leak site.

6. The method as set forth in claim 5, wherein the composition of matter includes an indicator which changes color in the presence of the gas escaping from the leak site, and wherein the step of changing color includes interacting the composition of matter with the gas escaping from the leak site to change the composition of matter at the leak site from the first color to the second color.

7. The method as set forth in claim 5, wherein the composition of matter includes water and an indicator which changes color in the presence of the gas escaping from the leak site and interacting with the water, and wherein the step of changing color includes interacting the water with the gas escaping from the leak site to change the color of the indicator at the leak site from the first color to the second color.

8. The method as set forth in claim 7, wherein the gas is one which, when it comes in contact with the water, alters the water'"'"'s pH.

9. The method as set forth in claim 8, wherein the indicator is a colorimetric pH indicator.

10. The method as set forth in claim 9, wherein the indicator is selected from the group including phenol red, bromothymol blue, neutral red, cresol red, azolitmin and naptholphthalein.

11. The method as set forth in claim 6, wherein the indicator is phenol red, the composition of matter is pinkish in color, and the gas is CO2, and wherein the CO2 escaping from the leak site changes the color of the composition of matter from pinkish to yellow at the leak site.

12. The method as set forth in claim 6, wherein the indicator is phenol red, the composition of matter is yellowish in color, and the gas is CO2, and wherein the CO2 escaping from the leak site changes the color of the composition of matter from yellowish to pinkish at the leak site.

13. The method as set forth in claim 8, wherein the gas is selected from the group including CO2, ammonia and sulfur dioxide.

14. The method as set forth in claim 1, wherein the step of covering includes the step of covering all of the surface area of the one or more external surfaces.

15. The method as set forth in claim 1, wherein the one or more external surfaces includes one or more of the group including seams, fittings, couplings and connectors (hereinafter “

connections”

), and wherein the step of covering includes the step of covering at least one of the one or more connections.

16. The method as set forth in claim 1, wherein the leak site is an opening having a cross sectional area less than the area of a 0.020″

diameter hole, and wherein the steps of injecting gas and covering the external surface in the area of the leak site determines the location of such leak site.

17. The method as set forth in claim 1, wherein the leak site is an opening having a cross sectional area down to at least the size of a hole 0.001″

in diameter, and wherein the steps of injecting gas and covering the external surface in the area of the leak site determines the location of such leak site.

18. The method as set forth in claim 1, wherein the composition of matter is one which foams, and wherein the step of covering takes the form of applying the foam to at least a portion of the one or more external surfaces.

19. The method as set forth in claim 1, further including the step of providing the source of gas with a pressure regulator, and wherein the method further includes the step of adjusting the pressure of the gas being injected into the sealed system.

20. The method as set forth in claim 1 further including providing a detector capable of detecting the presence of the gas, and wherein the method further includes the step of scanning at least some of the one or more external surfaces of the sealed system with the detector for the presence of the gas escaping from the leak site, to identify the base location of the leak site.

21. A method of detecting one or more leaks from a sealed system, the sealed system including one or more external surfaces, the method including the use of a source of pressurized gas external to the sealed system, a detector capable of detecting the presence of the gas, and a composition of matter which is capable of adhering to the one or more external surfaces and that will indicate the location of the leak site, the method including the steps of:

injecting gas from the external source into the sealed system to a pressure in excess of the pressure surrounding the sealed system;

canning with the detector at least some of the one or more external surfaces of the sealed system for the presence of the gas escaping from the at least one leak site in the sealed system to identify the base location of the leak; and

covering the external surface in the area of the base location with the composition of matter to identify the exact location of the leak.

22. The method as set forth in claim 21, wherein the composition of matter includes at least one surfactant capable of forming at least one bubble in the presence of gas escaping from the at lease one leak opening site, and wherein the method further includes the step generating one or more bubbles over the leak site by the interaction of the escaping gas with the at least one surfactant.

23. The method as set forth in claim 21, wherein the composition of matter has a first color that changes to a second color in the presence of the gas escaping from the leak site, and wherein the method further includes the step examining the composition of matter after it has been applied to locate the leak site by the presence of the second color around the leak site.

24. The method as set forth in claim 23, wherein the composition of matter includes water and an indicator which changes color in the presence of the gas escaping from the leak site and the water, and wherein the step of changing color includes interacting the water with the gas escaping from the leak site to change the color of the indicator at the leak site from the first color to the second color.

25. The method as set forth in claim 24, wherein the gas is one which, when it comes in contact with water, alters the water'"'"'s pH.

26. The method as set forth in claim 24, wherein the indicator is a colorimetric pH indicator and the gas is one that when in contact with water will alter the water'"'"'s pH.

27. A method of detecting leaks from one or more leak sites in a sealed system, the sealed system including one or more external surfaces, the method including the use of a source of pressurized gas external to the sealed system which gas is capable of passing through the one or more leak sites, the method further including the use of a detector including a housing and a sensor element capable of detecting the presence of the gas passing through the one or more leak sites, the method including the steps of:

injecting the gas from the external source into the sealed system to a pressure in excess of the pressure surrounding the sealed system; and

scanning with the detector over at least some of the one or more external surfaces of the sealed system for the presence of the gas escaping from at least one leak site in the sealed system to identify at least the base location of the leak.

28. The method as set forth in claim 27, wherein the detector also includes an alert system incorporated in the housing which is activated when the sensor element detects the presence of the gas escaping from the at least one leak site, and wherein the method includes the step of activating the alert system when the presence of the leaking gas is detected.

29. The method as set forth in claim 28, wherein the alert system includes an audio alert, and wherein the method includes the step of activating the audio alert when the presence of the leaking gas is detected.

30. The method as set forth in claim 28, wherein the alert system includes a visual alert, and wherein the method includes the step of activating the visual alert when the presence of the leaking gas is detected.

31. The method as set forth in claim 28, wherein the alert system includes both an audio alert and a visual alert, and wherein the method includes the step of activating the both alerts when the presence of the leaking gas is detected.

32. The method as set forth in claim 27, wherein the detector also includes an integral lighting system, and further including the step of illuminating the at least some of the one or more external surfaces as the sensor element is scanning.

33. The method as set forth in claim 27, wherein the one or more external surfaces include areas that are hard to reach, wherein the sensor is connected to the detector housing by a flexible connector which permits the sensor, as the detector is scanning, to scan the areas that are hard to reach, and wherein the step of scanning includes scanning at least some of the areas that are hard to reach with the sensor at the end of the flexible connector.

34. The method as set forth in claim 33, wherein the detector also includes an alert system which is activated when the sensor element detects the presence of the gas escaping from the at least one leak site, and wherein the method includes the step of activating the alert system when the presence of the leaking gas is detected.

35. The method as set forth in claim 34 wherein the time delay between detecting the presence of the gas escaping from the one leak site and the activation of the alert system is less than one second.

36. The method as set forth in claim 34, wherein the detector, including the housing, the alert system and the sensor element, is hand held.

37. The method as set forth in claim 27, wherein the step of scanning is scanning by moving the sensor element over the at least some of the one or more external surfaces of the sealed system.

38. The method set forth in claim 37, wherein the one or more external surfaces include areas that are hard to reach, wherein the sensor is connected to the detector housing by a flexible connector which permits the sensor to scan the areas that are hard to reach, and wherein the step of scanning includes scanning at least some of the areas that are hard to reach with the sensor at the end of the flexible connector.

39. The method of determining whether or not a sealed system is actually leaking, the sealed system including equipment for monitoring the system for leaks and indicating the presence of one or more leaks at one or more unspecified locations based on such monitoring, the method including the use of a source of pressurize gas external to the sealed system which gas is capable of passing through leak sites if, in fact, the system has one or more leak sites, the method further including the use of a detector including a sensing element designed to detect the presence of the gas, the method including the steps of:

injecting gas from the external source into the sealed system to a pressure in excess of the pressure surrounding the sealed system; and

scanning with the detector by moving the sensor element over at least some of the one or more external surfaces of the sealed system for the presence of the gas to determine if the sealed system is, in fact, leaking.

40. The method as set forth in claim 39, further including the step of sealing any leaks identified by the scanning if one or more leaks were identified.

41. The method as set forth in claim 39, further including the step of checking the monitoring equipment if no leaks were identified by the scanning step.

42. The method of determining whether or not a sealed system is actually leaking, the sealed system including one or more external surfaces and equipment for monitoring the system for leaks and indicating the presence of one or more leaks at one or more unspecified locations on the one or more external surfaces based on such monitoring, the method including the use of a source of pressurize gas external to the sealed system which gas is capable of passing through leak sites if, in fact, the system has one or more leak sites, the method further including the use of a composition of matter which is capable of adhering to at least portions of the one or more external surfaces and which is capable of identifying the presence of gas escaping from the sealed system if, in fact, the system has one or more leaks, the method including the steps of:

injecting gas from the external source into the sealed system to a pressure in excess of the pressure surrounding the sealed system; and

coating at least portions of the one or more external surfaces with the composition of matter to determine if the sealed system is, in fact, leaking.

43. The method as set forth in claim 42, further including the step of sealing any leaks identified by the scanning if one or more leaks were identified.

44. The method as set forth in claim 42, further including the step of checking the monitoring equipment if no leaks were identified by the scanning step.

45. A detector for identifying the presence of a gas leaking from a sealed system, the detector including:

a housing;

a sensor connected to the housing which is capable of detecting the presence of the gas leaking from the sealed system; and

an alert system, incorporated in the housing, which is activated when the sensor detects the presence of the gas.

46. The detector as set forth in claim 45, wherein the alert system includes both an audio and a visual alert.

47. The detector as set forth in claim 46, further including means to adjust the sensitivity of at least one of the audio and visual alerts.

48. The detector as set forth in claim 45, further including lighting means for illuminating the area proximate to the sensor, the lighting means included in the housing.

49. The detector as set forth in claim 45, wherein the sensor is a Nerst Cell.

50. The detector as set forth in claim 45, wherein the sensor is connected to the housing by a flexible connector.

51. A composition of matter for detecting the presence of a gas which will react with water to alter the water'"'"'s pH by acting in at least one of the ways selected from the group comprising forming at least one bubble in the presence of the gas and changing the color of the composition of matter in the presence of the gas, the composition including:

water;

a surfactant; and

a colorimetric pH indicator.

52. The composition of matter as set forth in claim 51, wherein the colorimetric pH indicator is selected from the group including bromothymol blue, neutral red, cresol red, phenol red, azolitmin and naptholphthalein.

53. An aerosol foam comprising;

an aerosol container including a nozzle;

a composition of matter stored in the container which foams when applied to a surface, the composition of matter including water, a surfactant and a colorimetric pH indicator; and

a gas propellant stored in the container which does not react with the composition of matter and insures that the colorimetric pH indicator stays above a preselected pH value while the composition of matter is stored in the container.