Flow and pipe management using velocity profile measurement and/or pipe wall thickness and wear monitoring

• US 9,404,893 B2
• Filed: 03/16/2009
• Issued: 08/02/2016
• Est. Priority Date: 03/14/2008
• Status: Active Grant

• Current Assignee: Cidra Corporate Services, Inc.
• Original Assignee: Cidra Corporate Services, Inc.
• Inventors: O'Keefe, Christian, Maron, Robert J., Fernald, Mark R., Bailey, Timothy J., Van der Spek, Alex, Davis, Michael A., Viega, John V.
• Primary Examiner(s): Larkin, Daniel S
• Assistant Examiner(s): MILLER, ROSE MARY
• Application Number:
  US12/922,261
• Publication Number:
  US 20110056298A1
• Time in Patent Office: 2,696 Days
• Field of Search: 736/22, 736/24, 736/25, 736/26, 736/28, 736/37
• US Class Current: 1/1
• CPC Class Codes: G01B 17/02 for measuring thickness
• CPC Class Codes: G01N 29/04 Analysing solids using acoustic emission techniques G01N29/14
• CPC Class Codes: G01N 29/2437 Piezoelectric probes

Abstract

The present invention provides new techniques for non-invasive and real-time measurement of the velocity profile of slurry flow in horizontal pipes, as well as the measurement and trending of pipe wear on slurry lines. In the first case, this information can be used to determine the approach and onset of solid deposition on the bottom of the pipe. Having this information in real time can enable operation at lower velocities or higher solids concentration or both while avoiding solids deposition or plugging and their associated operational costs. In the second case, the present invention uses a permanently or semi-permanently installed ring of conformable ultrasonic transducers clamped onto the outside of the pipe. These transducers are used to measure the thickness of the pipe under their respective locations.

Claims

1. Apparatus for determining a thickness of a wall of a pipe, characterised in that the apparatus comprises:

a signal processing module configured to

respond to signaling containing information about traveling stress waves transmitted to and reflected back from an inner surface and an outer surface of a wall of a pipe by a sensor band that includes a series, ring or array having multiple PVDF transducers circumferentially arranged at angular positions and mounted around, and attached to or clamped onto, the outer surface of the wall of the pipe, the signaling being generated over a period of time by each of the multiple PVDF transducers in the sensor band that transmits respective traveling stress waves and senses reflections of the respective traveling stress waves transmitted that are reflected back from the inner surface a certain time later than from the outer surface at each circumferential location of a respective one of the multiple PVDF transducers; and

determine corresponding signaling containing information about a time-based trending profile of a thickness of the wall of the pipe corresponding to respective circumferential locations of the multiple PVDF transducers as a function of the angular position and the period of time, based on the signaling received over the period of time from the sensor band using a self-reference approach where the difference in time between the reflections of the traveling stress waves being reflected back from the inner surface and the outer surface is proportional to the thickness of the wall of the pipe.

2. Apparatus according to claim 1, wherein the signal processing module makes the determination based at least partly on the time traveling stress waves travel to and are reflected back from the inner surface and the outer surface of the wall of the pipe.

3. Apparatus according to claim 1, wherein the signal processing module provides the corresponding signaling containing information about the profile of the thickness of the wall of the pipe.

4. Apparatus according to claim 3, wherein the corresponding signaling contains information about a graph to provide a visual indication of the thickness of the wall of the pipe.

5. Apparatus according to claim 4, wherein the graph is a polar plot that provides the thickness of the wall of the pipe as a function of the angular distance from a set reference point of the pipe.

6. Apparatus according to claim 1, wherein the signal processing module provides an input signal to the multiple PVDF transducers.

7. Apparatus according to claim 1, wherein each PVDF transducer propagates a respective traveling stress wave to the inner surface and the outer surface of the wall of the pipe.

8. Apparatus according to claim 1, wherein the apparatus comprises the sensor band that includes the series, ring or array of the multiple PVDF transducers that are permanently or semi-permanently mounted around, attached to or clamped onto, the outer surface of the wall of the pipe.

9. Apparatus according to claim 8, wherein the signal processing module determines an interpolation of the thickness of the wall of the pipe between one or more pairs of sensor points in the series, ring or array of the multiple PVDF transducers.

10. Apparatus according to claim 9, wherein the signal processing module determines a substantially continuous wall thickness prediction around the wall of the pipe.

11. Apparatus according to claim 9, wherein the signal processing module determines a future pipe condition prediction around the wall of the pipe, based at least partly on the orientation of the pipe.

12. Apparatus according to claim 11, wherein the signal processing module determines a future pipe condition prediction by an extrapolation technique, based at least partly determining a calculated wear model or profile using some combination of a least-square polynomial extrapolation and Fourier component extrapolation.

13. Apparatus according to claim 11, wherein the signal processing module determines a lifetime schedule or a rotation schedule for the pipe, based at least partly on either when or at which angle the pipe should be rotated so as to distribute substantially equally the wear of the pipe around the inner wall of the pipe.

14. Apparatus according to claim 11, wherein the signal processing module determines trigger points that can be used to predict certain wall thickness configurations requiring intervention from maintenance personnel.

15. Apparatus according to claim 9, wherein the interpolation is determined using curve fitting routines that include cubic spline or polynomial regression techniques, or a Fourier decomposition technique.

16. Apparatus according to claim 15, wherein when implementing the Fourier decomposition technique, the signal processing module determines various Fourier components required to create a curve which includes sample or sensor points and determines intermediate locations between the sample or sensor points.

17. Apparatus according to claim 16, wherein the signal processing module uses custom tailored weighting coefficients on the Fourier components.

18. Apparatus according to claim 16, wherein the signal processing module limits the magnitude of one or more derived Fourier components to physically realistic value points so as to identify and discard a derived Fourier component from a data set.

19. Apparatus according to claim 8, wherein the multiple PVDF transducers are equally spaced circumferentially around the outer surface of the wall of the pipe so as to provide a complete profile of the thickness of the wall of the pipe.

20. Apparatus according to claim 1, wherein each PVDF transducer responds to an input signal from the signal processing module and transmits a respective traveling stress wave to the inner surface and the outer surface of the wall of the pipe.

21. Apparatus according to claim 20, wherein each PVDF transducer responds to a respective traveling stress wave reflected off the inner surface and the outer surface of the wall of the pipe and returned back to said each PVDF transducer, and provides a respective output signal containing information about the same that can be used to determine the thickness of the wall of the pipe.

22. Apparatus according to claim 1, wherein the signal processing module is configure to determine the thickness of the wall of a steel pipe or a polymer pipe.

23. Apparatus according to claim 1, wherein the signal processing module is configured to determine an absolute thickness of the wall of the pipe.

24. Apparatus according to claim 1, wherein the signal processing module is configured to determine a relative thickness of the wall of the pipe, based at least partly on a pipe wall thickness trend that includes at least one comparison of the thickness of the wall of the pipe performed at two different periods of time.

25. Apparatus according to claim 1, wherein the apparatus comprises the sensor band that includes the series, ring or array having the multiple PVDF transducers circumferentially arranged and mounted around, and attached to or clamped onto, the outer surface of the wall of the pipe, each PVDF transducer configured to generated respective traveling stress waves at a respective circumferential location, and sense reflections of the respective traveling stress waves at the respective circumferential location.

26. Apparatus according to claim 1, wherein the signal processing module forms part of either a portable device hand carried to the series, ring or array of multiple PVDF transducers, or is mounted near or next to the series, ring or array of multiple PVDF transducers.

27. Apparatus according to claim 1, wherein at least one PVDF transducer is an ultrasonic signal transmitter and receiver that receives an input signal from the signal processing module, and provides the signaling containing information about the traveling stress waves transmitted to and reflected back from the wall of the pipe.

28. Apparatus according to claim 1, wherein one or more of the multiple PVDF transducers comprises two parts, a first part being a PVDF transducer part, and a second part being a spacer.

29. Apparatus according to claim 28, wherein the PVDF transducer part injects the traveling stress waves into the spacer so as to travel to the wall of the pipe, such that some traveling stress waves hit the outer surface of the wall of the pipe and some amount thereof is reflected back, and other traveling stress waves hit the inner surface of the wall of the pipe and some other amount thereof is reflected back at the certain time later.

30. Apparatus according to claim 28, wherein the PVDF transducer part injects the traveling stress waves into the wall of the pipe that will continue to bounce back-and-forth producing a series, ring or circumferential array of equally spaced pulses, and where the thickness of the wall of the pipe is determined by the time between successive pulses being measured, so as to eliminate the requirement for absolute timing based on the injected pulse.

31. Apparatus according to claim 28, wherein the PVDF transducer part detects received pulses with any one or more signal processing techniques, based at least partly on either a simple peak detection, or a quadrature, homodyne or heterodyne demodulation.

32. Apparatus according to claim 1, wherein the signal processing module makes the determination based on an orientation of the sensor band around the outer surface of the wall of the pipe.

33. Apparatus according to claim 32, wherein the signal processing module makes the determination based on a recordation of data related to the orientation of the sensor band around the surface of the wall of the pipe.

34. Apparatus according to claim 1, wherein the apparatus comprises a compression band arranged to compress the sensor band against the outer surface of the wall of the pipe.

35. Apparatus according to claim 34, wherein the apparatus comprises a compliant backing material arranged between the compression band and the sensor band to cushion and allow the sensor band to conform to the shape of the outer surface of wall of the pipe.

36. Apparatus according to claim 1, wherein the sensor band is attached to the outer surface of the wall of the pipe using a couplant taking the form of a gel, so as to substantially eliminate air pockets and maximize a signal path between the sensor band and the outer surface of the outside wall of the pipe.

37. Apparatus according to claim 1, wherein the profile is a complete profile corresponding to the multiple PVDF transducers circumferentially arranged around the outer surface of the wall of the pipe.

38. Apparatus according to claim 1, wherein the signal processing module is configured to determine an interpolation of the thickness of the wall of the pipe between at least one adjacent pair of the multiple PVDF transducers in the series, ring or array.

39. Apparatus according to claim 1, wherein the period of time is measured in weeks or months.

40. Apparatus according to claim 1, wherein the corresponding signaling includes a plurality of respective time-based profiles determined during the period of time.

41. Apparatus for determining a thickness of a wall of a pipe, comprising:

a signal processing module that

responds to signaling containing information about traveling stress waves transmitted to and reflected back from an inner surface and an outer surface of a wall of a pipe by a sensor band having multiple PVDF transducers circumferentially arranged at angular positions and mounted around a perimeter of the wall of the pipe, the signaling being generated over a period of time by each of the multiple PVDF transducers in the sensor band that transmits respective traveling stress waves and senses reflections of the respective traveling stress waves transmitted that are reflected back from the inner surface a certain time later than from the outer surface;

determines corresponding signaling containing information about a time-based trending profile of a thickness of the wall of the pipe corresponding to the respective circumferential locations of the multiple PVDF transducers as a function of the angular position and the period of time, based on the signaling received from the sensor band using a self-reference approach where the difference in time between the reflections of the traveling stress waves being reflected back from the inner surface and the outer surface is proportional to the thickness of the wall of the pipe; and

provides an input signal containing information about an adjustment to the frequency of the traveling stress waves propagated through the inner surface and the outer surface of the wall of the pipe based at least partly on the signal-to-noise ratio of the signaling received.

42. Apparatus for determining a thickness of a wall of a pipe, comprising:

a signal processing module that

responds to signaling containing information about traveling stress waves transmitted to and reflected back from an inner surface and an outer surface of a wall of a pipe by a sensor band having multiple PVDF transducers circumferentially arranged at angular positions and mounted around a perimeter of the wall of the pipe, the signaling being generated over a period of time by each of the multiple PVDF transducers in the sensor band that transmits respective traveling stress waves and senses reflections of the traveling stress waves transmitted that are reflected back from the inner surface a certain time later than from the outer surface, and

determines corresponding signaling containing information about a time-based trending profile of a thickness of the wall of the pipe corresponding to the respective circumferential locations of the multiple PVDF transducers as a function of the angular position and the period of time, based on the signaling received from the sensor band using a self-reference approach where the difference in time between the reflections of the traveling stress waves being reflected back from the inner surface and the outer surface is proportional to the thickness of the wall of the pipe; and

an ultrasonic signal pulser and receiver that adjusts the frequency of at least one traveling stress wave propagated through the inner surface and the outer surface of the wall of the pipe by modulating the phase of an ultrasonic signal with an m-sequence code.

43. Apparatus according to claim 42, wherein the ultrasonic signal pulser and receiver correlates the m-sequence code with a known code and to detect a desired signal from system noise and other non-coherent reflections.

44. Apparatus for determining a thickness of a wall of a pipe, comprising:

a signal processing module that

responds to signaling containing information about traveling stress waves transmitted to and reflected back from an inner surface and an outer surface of a wall of a pipe by a sensor band having multiple PVDF transducers circumferentially arranged at angular positions and mounted around a perimeter of the wall of the pipe, the signaling being generated over a period of time by each of the multiple PVDF transducers in the sensor band that transmits respective traveling stress waves and senses reflections of the traveling stress waves transmitted that are reflected back from the inner surface a certain time later than from the outer surface, and

determines corresponding signaling containing information about a time-based trending profile of a thickness of the wall of the pipe corresponding to the respective circumferential locations of the multiple PVDF transducers based on the signaling received from the sensor band using a self-reference approach where the difference in time between the reflections of the traveling stress waves being reflected back from the inner surface and the outer surface is proportional to the thickness of the wall of the pipe; and

one or more orientation or rotation sensors, each responding to its orientation in relation to its displacement on the pipe and to provide an orientation signal containing information about the same.

45. Apparatus according to claim 44, wherein the one or more orientation or rotation sensors provides the orientation signal back to the signal processing module.

46. Apparatus according to claim 44, wherein the signal processing module is configured to receive the orientation signal containing information about an angular position of at least one orientation sensor arranged on the pipe.

47. Apparatus according to claim 44, wherein the signal processing module is configured to receive and use the orientation signal to calculate variable wear rates at different positions on the pipe, based at least partly on the fact that heavier materials tend to travel along the bottom of the pipe and induce greater wear in that location.

48. Apparatus according to claim 44, wherein the one or more orientation or rotation sensors comprise at least two orientation or rotation sensors spaced along the sensor band and around the pipe to provide orientation data.

49. Apparatus according to claim 44, wherein the signal processing module is configured to receive and use the orientation signal to predict a pipe future condition, based at least partly on the orientation signal received.