Non-invasive pipeline inspection system

• US 6,751,560 B1
• Filed: 09/06/2000
• Issued: 06/15/2004
• Est. Priority Date: 08/01/2000
• Status: Active Grant

• Current Assignee: Charles Stark Draper Laboratory Incorporated
• Original Assignee: Charles Stark Draper Laboratory Incorporated
• Inventors: Tingley, Robert, Brancart, Claude P.
• Primary Examiner(s): Barlow, John
• Assistant Examiner(s): Lau, Tung S
• Application Number:
  US09/655,954
• Time in Patent Office: 1,378 Days
• Field of Search: 702/51, 736/29, 736/32, 736/20, 736/38, 736/43, 324/639, 324/633, 324/635, 359/125, 367/35, 219/687, 219/679, 204/157
• US Class Current: 702/51
• CPC Class Codes: G01N 22/02 Investigating the presence of flaws
• CPC Class Codes: G01N 2291/2636 cylindrical from inside
• CPC Class Codes: G01N 2291/2675 Seam, butt welding
• CPC Class Codes: G01N 29/11 by measuring attenuation of acoustic waves
• CPC Class Codes: G01N 29/348 with frequency characteristics, e.g. single frequency signals, chirp signals measuring frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04; measuring frequency or analysing frequency spectra G01R23/00
• CPC Class Codes: G01N 29/4463 Signal correction, e.g. distance amplitude correction [DAC], distance gain size [DGS], noise filtering
• CPC Class Codes: G01N 29/46 by spectral analysis, e.g. Fourier analysis or wavelet analysis spectral signal processing per se G06F17/14

Abstract

The invention is directed to a system and method for non-invasive pipeline inspection. According to one embodiment, the system includes a processor, an analyzer, and a wave launcher. The wave launcher is adapted to transmit an input wideband waveform having a selected input energy into the pipeline along a longitudinal axis, and to receive from the pipeline a reflected component of the input waveform having a reflected energy. The analyzer is adapted to generate the input waveform, and to receive the reflected component of the input waveform from the wave launcher. The processor is adapted to compare the input waveform with the reflected component of the input waveform to determine characteristics.

Claims

1. A pipeline inspection system comprising,

a wave launcher in communication with a pipeline and adapted to transmit an input waveform having a selected input energy along a longitudinal axis inside said pipeline, and to receive a reflected component of said input waveform from said pipeline, said reflected component having a characteristic reflected energy,

an analyzer in communication with said wave launcher and adapted to generate said input waveform, and to receive said reflected component of said input waveform from said wave launcher, and

a processor in communication with said analyzer and adapted to compare said input waveform with said reflected component of said input waveform to determine a characteristic of said pipeline,

wherein the wave launcher, the analyzer, and the processor operate in a fashion that is non-invasive to the pipeline.

2. The apparatus of claim 1, wherein said processor is further adapted to compare said input waveform with said reflected component to detect an anomaly in said pipeline.

3. The apparatus of claim 1, wherein said processor is further adapted to compare said input waveform with said reflected component to determine an axial curvature in said pipeline.

4. The apparatus of claim 1, wherein said processor is further adapted to compare said input waveform with said reflected component to determine location points along said pipeline relative to an initial known location.

5. The apparatus of claim 1, wherein said wave launcher further comprises a probe antenna, said probe antenna adapted for transmitting said input waveform into said pipeline.

6. The apparatus of claim 1, wherein said analyzer is further adapted to detect said reflected component along said longitudinal axis of said pipeline.

7. The apparatus of claim 1, wherein said processor is further adapted to generate a mathematical model representative of said pipeline.

8. The apparatus of claim 1, wherein said analyzer is further adapted to extract a characteristic energy and phase for said input waveform and said reflected component.

9. The apparatus of claim 1, wherein said analyzer is further adapted to generate said input waveform with a frequency above a characteristic cutoff frequency of said pipeline.

10. The apparatus of claim 1, wherein said analyzer is further adapted to generate said input waveform at a frequency within a range of frequencies for which a dominant mode for said pipeline exists.

11. The apparatus of claim 1, wherein said analyzer is further adapted to generate an electromagnetic waveform as said input waveform.

12. The apparatus of claim 1, wherein said analyzer is further adapted to generate an acoustic waveform as said input waveform.

13. The apparatus of claim 1, wherein said analyzer is further adapted to generate said input waveform as one of a spread spectrum waveform, a chirp waveform, and a soliton waveform.

14. The apparatus of claim 1, wherein said analyzer is further adapted to generate said input waveform as wideband waveform.

15. The apparatus of claim 1 further comprising calibration elements adapted to temperature stabilize said analyzer.

16. The apparatus of claim 2, wherein said anomaly is at least one of a crack, a corrosion, a leak, a location of an end wall, an obstruction, a flange, a weld, and a restriction in said pipeline.

17. The apparatus of claim 2, wherein said processor is further adapted to compare said input waveform with said reflected component to determine a location of said anomaly in said pipeline.

18. The apparatus of claim 2, wherein said processor is further adapted to compare said input waveform with said reflected component to determine a shape of said anomaly in said pipeline.

19. The apparatus of claim 2, wherein said processor is further adapted to compare said input waveform with said reflected component to determine one of an absolute size of said anomaly and a relative size of said anomaly relative to an internal diameter of said pipeline.

20. The apparatus of claim 5, wherein said probe antenna of said wave launcher is in physical contact with said pipeline.

21. The apparatus of claim 7, wherein said mathematical model is ideal.

22. The apparatus of claim 7, wherein said mathematical model is lossy.

23. The apparatus of claim 7, wherein said mathematical model is one of an averaging model and a cross-sectional model.

24. The apparatus of claim 7, wherein said processor is further adapted to generate a model transfer function relating a model input waveform to a model reflected component, an actual transfer function relating an actual input waveform to an actual reflected component, and to determine said characteristic at least in part by comparing said model transfer function with said actual transfer function.

25. The apparatus of claim 7, wherein said processor is further adapted to determine said characteristic of said pipeline at least in part by comparing an actual reflected component with a model reflected component.

26. The apparatus of claim 10, wherein said input waveform comprises a plurality of input signals within said range of frequencies.

27. The apparatus of claim 26, wherein said analyzer is further adapted to detect differences in velocity between said plurality of input signals as said input signals propagate in said pipeline, and said processor is further adapted to determine a curvature of said pipe along said longitudinal axis from said differences in velocity.

28. The apparatus of claim 26, wherein said analyzer is further adapted to detect differences in velocity between reflected components of each of said plurality of input signals to determine a curvature of said pipeline along said longitudinal axis.

29. A method of inspecting a characteristic of a pipeline, said method comprising,

transmitting an input waveform having a selected input energy along a longitudinal axis inside said pipeline,

receiving a reflected component of said input waveform from said pipeline, said reflected component having a characteristic reflected energy, and

comparing said input waveform with said reflected component of said input waveform to determine said characteristic of said pipeline,

wherein the transmitting, receiving, and comparing steps occur in a fashion that is non-invasive to the pipeline.

30. The method of claim 29 further comprising, comparing said input waveform with said reflected component to detect an anomaly in said pipeline.

31. The method of claim 29 further comprising, comparing said input waveform with said reflected component to determine an axial curvature in said pipeline.

32. The method of claim 29 further comprising, comparing said input waveform with said reflected component to determine location points along said pipeline relative to an initial known location.

33. The method of claim 29, further comprising, detecting said reflected component along said longitudinal axis of said pipeline.

34. The method of claim 29 further comprising, generating a mathematical model representative of said pipeline.

35. The method of claim 29 further comprising, extracting a characteristic energy and phase for said input waveform and said reflected component.

36. The method of claim 29 further comprising, generating said input waveform with a frequency above a characteristic cutoff frequency of said pipeline.

37. The method of claim 29 further comprising, generating said input waveform at a frequency within a range of frequencies for which a dominant mode for said pipeline exists.

39. The method of claim 29 further comprising, generating an acoustic waveform as said input waveform.

40. The method of claim 29 further comprising, generating said input waveform as one of a spread spectrum waveform, a chirp waveform, and a soliton waveform.

41. The method of claim 29 further comprising, generating said input waveform as a wideband waveform.

42. The method of claim 29 further comprising, calibrating said analyzer to be temperature stable.

43. The method of claim 30, wherein said anomaly is at least one of a crack, a corrosion, a leak, a location of an end wall, an obstruction, a flange, a weld, and a restriction in said pipeline.

44. The method of claim 30 further comprising, comparing said input waveform with said reflected component to determine a location of said anomaly in said pipeline.

45. The method of claim 30 further comprising, comparing said input waveform with said reflected component to determine a shape of said anomaly in said pipeline.

46. The method of claim 30 further comprising, comparing said input waveform with said reflected component to determine one of an absolute size of said anomaly and a relative size of said anomaly relative to an internal diameter of said pipeline.

47. The method of claim 34, wherein said mathematical model is ideal.

48. The method of claim 34, wherein said mathematical model is lossy.

49. The method of claim 34, wherein said mathematical model is one of an averaging model and a cross-sectional model.

50. The method of claim 34 further comprising, generating a model transfer function relating a model input waveform to a model reflected component, an actual transfer function relating an actual input waveform to an actual reflected component, and to determine said characteristic at least in part by comparing said model transfer function with said actual transfer function.

51. The method of claim 34 further comprising, determining said characteristic of said pipeline at least in part by comparing an actual reflected component with a model reflected component.

52. The method of claim 37, wherein said input waveform comprises a plurality of input signals within said range of frequencies.

53. The method of claim 37 further comprising, detecting differences in velocity between said plurality of input signals as said input signals propagate in said pipeline, and determining a curvature of said pipe along said longitudinal axis from said differences in velocity.

54. The method of claim 52 further comprising, detecting differences in velocity between reflected components of each of said plurality of input signals to determine a curvature of said pipeline along said longitudinal axis.

38. The method of 29 further comprising, generating an electromagnetic waveform as said input waveform.

55. A method of determining a location of a point along a pipeline, said method comprising,

transmitting an input waveform having a selected input energy along a longitudinal axis inside said pipeline,

receiving a reflected component of said input waveform from said pipeline, said reflected component having a characteristic reflected energy, and

comparing said input waveform with said reflected component of said input waveform to determine said location of said point along said pipeline,

wherein the transmitting, receiving, and comparing steps occur in a fashion that is non-invasive to the pipeline.

56. A method of inspecting a characteristic of a pipeline, said method comprising,

generating an input waveform,

launching said input waveform along a longitudinal axis inside said pipeline,

receiving from said pipeline a reflected component having a characteristic reflected energy of said input waveform,

calculating a mathematical function of said characteristic reflected energy from said reflected component of said input waveform,

determining a model mathematical function of model reflected energy from a model component of a model input waveform, and

determining said characteristic of said pipeline by comparing said mathematical function of said reflected energy to said model mathematical function of said model reflected energy,

wherein each step is performed in a fashion that is non-invasive to the pipeline.