System and method to accomplish pipeline reliability

• US 20030171879A1
• Filed: 03/08/2002
• Published: 09/11/2003
• Est. Priority Date: 03/08/2002
• Status: Abandoned Application

• Current Assignee: Arizona Public Service Company (Pinnacle West Capital Corporation)
• Original Assignee: Arizona Public Service Company (Pinnacle West Capital Corporation)
• Inventors: Pittalwala, Shabbir H., Wittas, Daniel J.
• Application Number:
  US10/093,620
• Publication Number:
  US 20030171879A1
• Time in Patent Office: Days
• US Class Current: 702/34
• CPC Class Codes: F17D 5/00 Protection or supervision of installations arrangements for protecting foundations E02D31/00; protecting pipes from damage or internal or external wear F16L57/00, against corrosion and scale F16L58/00; investigation of the fluid-tightness of structures G01M3/00

Abstract

A system and method is disclosed for facilitating the management of pipeline reliability, maintenance, repair, and/or replacement. Embodiments may be computer-implemented, and may be suitable for prestressed concrete cylinder pipe (e.g., PCCP). Method steps include inspecting the pipe and storing or inputting design and inspection parameters, as well as the maximum expected pressure within the pipe. A relation of pressure versus degradation (e.g., number of broken wires) may be used, which may have zones of risk or classifications corresponding to pipe management actions. The pipe may be analyzed for lack of prestress over various portions of circumference and length. The pipe rupture pressure, crack onset pressure, or can rupture pressure may be analyzed and compared to the expected pressure. The method may be tested and the inspection repeated while tracking changes. The action may involve, for instance, doing nothing, monitoring the pipe, repairing the pipe, or replacing the pipe.

Claims

1. A method of facilitating the determination of whether to take pipe management action, the method comprising, in any order, at least the steps of:

acquiring a first parameter, the first parameter being a design parameter for the pipe;

inspecting the pipe at least a first time;

acquiring a second parameter, the second parameter being an inspection parameter comprising at least an evaluation of the structural integrity of the pipe;

acquiring a third parameter, the third parameter comprising at least a pressure within the pipe; and

using at least a relation of the evaluation of the structural integrity of the pipe and the pressure within the pipe, facilitating a determination of whether or not to take pipe management action.

2. The method according to claim 1:

the pipe having a diameter;

the first parameter comprising at least the diameter of the pipe;

the pressure within the pipe being substantially a maximum pressure anticipated within the pipe in future service;

the method further comprising at least a step of facilitating a determination of when to take pipe management action.

3. The method according to claim 1 further comprising at least the steps of:

waiting until the next time to inspect;

inspecting the pipe at least a second time; and

acquiring at least a fourth parameter, the fourth parameter being an inspection parameter comprising at least an evaluation of the structural integrity of the pipe at the second time.

4. The method according to claim 3 further comprising at least the step of:

calculating a degradation rate of the pipe;

the degradation rate being determined from the difference in the structural integrity of the pipe from the first time to the second time.

5. The method according to claim 4:

the pipe being prestressed concrete cylinder pipe;

the second parameter comprising at least a quantity of broken wires; and

the method further comprising at least the step of using the degradation rate of the pipe, calculating when the pipe should be repaired or replaced.

6. The method according to claim 5, said inspecting comprising at least eddy current inspection.

7. The method according to claim 1:

the pipe being prestressed concrete cylinder pipe, and

the second parameter comprising at least a quantity of broken wires.

8. The method according to claim 1, the pipe management action being selected from the group consisting of repairing, replacing, and monitoring the pipe.

9. The method according to claim 1, said inspecting comprising at least eddy current inspection.

10. The method according to claim 1, said inspecting comprising at least ultrasonic inspection.

11. The method according to claim 1, said inspecting comprising at least visual inspection and sounding.

12. The method according to claim 1:

the relation being embedded within a computer program; and

the relation having at least a plurality of zones of risk.

13. The method according to claim 1 further comprising at least the step of testing the method over time to verify that it works.

14. A system for facilitating a determination of whether to take pipe management action, the system comprising at least:

a relation of pressure versus a quantification of the degradation of the structural integrity of the pipe;

said relation being at least one of;

a physically-viewable graph,

an algorithm stored within a computer, and

data stored within a computer; and

said relation having at least;

;

a zone of higher risk, and

a zone of lower risk.

15. The system according to claim 14, the pressure being maximum anticipated pressure within the pipe.

16. The system according to claim 14, the relation further having at least a zone of medium risk, the zone of medium risk being between the zone of higher risk and the zone of lower risk.

17. The system according to claim 14, the pipe being prestressed concrete cylinder pipe.

18. The system according to claim 17, the quantification of the degradation of the structural integrity of the pipe comprising at least a quantity of broken wires.

19. The system according to claim 18, the relation further comprising at least the anticipated pressure for the ultimate strength of the cylinder.

20. The system according to claim 14:

the pipe comprising at least a concrete core; and

the relation comprising at least;

the anticipated rupture pressure of the pipe; and

the pressure anticipated to cause the concrete core to crack.

21. The system according to claim 20, the relation further comprising at least:

an action pressure;

the action pressure being less than the anticipated rupture pressure of the pipe; and

the action pressure being greater than the pressure anticipated to cause the concrete core to crack.

22. A method of facilitating the management of a pipeline, the pipeline comprising at least a plurality of sections of prestressed concrete cylinder pipe, the method comprising, in any order, at least the steps of:

storing design data for each of at least a plurality of the sections, the design data comprising at least one dimension of each section;

inspecting at least a plurality of the sections, said inspecting comprising at least evaluating the quantity of failed wires within the sections;

estimating the maximum pressure that is likely to exist in future service within each of at least a plurality of the sections;

using at least the design data, the quantity of failed wires, and the maximum pressure, designating a classification for the condition of at least a plurality of the sections; and

implementing pipe management action based on at least one classification.

23. The method according to claim 22, the design data further comprising at least external loading on at least one of the sections.

24. The method according to claim 22, said inspecting being repeated at different times, the method further comprising at least the step of tracking changes in the quantity of failed wires over time for at least a plurality of sections.

26. The method according to claim 22, the action being selected from the group consisting of:

monitoring the section, repairing the section, and replacing the section.

27. The method according to claim 22, each classification having a corresponding action:

the method comprising at least two classifications, the two classifications being a first classification and a second classification;

the action corresponding to the first classification being doing nothing to the section, at least until the next inspection; and

the action corresponding to the second classification being selected from the group consisting of;

repairing at least the section and replacing at least the section.

28. The method according to claim 22, each classification having a corresponding action:

the method comprising at least three classifications, the three classifications being a first classification, a second classification, and a third classification;

the action corresponding to the first classification being doing nothing to the section, at least until the next inspection;

the action corresponding to the second classification being monitoring at least the section; and

the action corresponding to the third classification being selected from the group consisting of;

repairing at least the section and replacing at least a plurality of adjacent sections.

29. The method according to claim 22 further comprising at least the step of analyzing at least one of the sections for lack of prestress pressure:

over the section'"'"'s entire circumference; and

over a limited length of the section.

30. The method according to claim 22 further comprising at least the step of analyzing at least one of the sections for lack of prestress pressure:

over just a portion of the section'"'"'s circumference; and

over a limited length of the section.

31. The method according to claim 22 further comprising at least the step of analyzing at least one of the sections for lack of prestress pressure:

over a first limited length of the section; and

over a second limited length of the section;

a segment of pipe with intact prestressed wire being located between the first limited length and the second limited length.

32. The method according to claim 31:

the segment being more than 3-inches long;

the segment being less than 25-inches long; and

the effective length of failed wires being a function of;

the first limited length,

the second limited length, and

the length of the segment.

33. The method according to claim 22 further comprising at least the step of analyzing the rupture pressure of at least one of the sections.

34. The method according to claim 33, the designating a classification comprising at least determining whether the maximum pressure exceeds the rupture pressure of the section.

35. The method according to claim 33, the designating a classification comprising at least determining whether the maximum pressure exceeds, by more than a predetermined non-zero amount, the rupture pressure of the section.

36. The method according to claim 33 further comprising at least the step of analyzing crack onset pressure.

37. The method according to claim 36, the designating a classification comprising at least determining whether:

the maximum pressure is less than the rupture pressure of the section; and

the maximum pressure exceeds the crack onset pressure.

38. The method according to claim 36:

the designating a classification comprising at least analyzing an action pressure;

the action pressure being less than the rupture pressure of the section;

the action pressure being greater than the crack onset pressure of the section; and

the designating a classification comprising at least determining whether the maximum pressure is greater than or less than the action pressure of the section.

39. The method according to claim 38, the designating a classification comprising at least determining whether the maximum pressure is less than the rupture pressure of the cylinder.

40. The method according to claim 22:

said inspecting being repeated at different times,

the method further comprising at least the step of tracking changes in the quantity of failed wires over time;

each classification having a corresponding action

the method further comprising at least the steps of;

calculating for at least a plurality of sections the rate of wire failures, and

predicting when a plurality of sections of the pipeline will enter a lower classification;

the method comprising at least two classifications, the two classifications being a first classification and a second classification;

the action corresponding to the first classification being doing nothing, at least until the next inspection; and

the action corresponding to the second classification being selected from the group consisting of;

monitoring the section, repairing the section, and replacing at least a plurality of adjacent sections.

41. The method according to claim 40:

further comprising at least the step of analyzing at least one section for lack of prestress pressure;

over the section'"'"'s entire circumference, and

over a limited length of the section;

further comprising at least the step of analyzing at least one section for lack of prestress pressure;

over just a portion of the section'"'"'s circumference, and

over a limited length of the section;

further comprising at least the step of analyzing at least one section for lack of prestress pressure;

over the section'"'"'s entire circumference,

over a first limited length of the section, and

over a second limited length of the section,

a segment of pipe with intact prestressed wire being located between the first limited length and the second limited length.

42. The method according to claim 40:

further comprising at least the step of analyzing the rupture pressure of at least one section;

the designating a classification comprising at least determining whether the maximum pressure exceeds the rupture pressure of the section;

the designating a classification comprising at least the step of analyzing the crack onset pressure of the section; and

the designating a classification comprising at least determining whether the maximum pressure exceeds the crack onset pressure.

25. The method according to claim 25, each classification having a corresponding action, the method further comprising at least the steps of:

calculating the rate of wire failures for at least a plurality of the sections; and

predicting when at least one of the sections will enter another classification.

43. A computer implemented system for facilitating a determination of whether to take pipe management action, the system comprising at least:

a processor, said processor being configured to;

acquire a first parameter, the first parameter being a design parameter for the pipe;

acquire a second parameter, the second parameter being an inspection parameter comprising at least information indicating the degradation of the structural integrity of the pipe;

acquire a third parameter, the third parameter comprising at least a pressure within the pipe; and

using at least a relation of the second parameter and the third parameter, output information to facilitate determining at least whether or not to take pipe management action.

44. The system according to claim 43:

the pipe having a diameter;

the first parameter comprising at least the diameter of the pipe;

the pressure within the pipe being substantially a maximum pressure anticipated in future service;

the processor further being configured to output information to facilitate determining when to take pipe management action.

45. The system according to claim 43 the processor being further configured to:

acquire at least a fourth parameter, the fourth parameter being an inspection parameter comprising at least information indicating the degradation of the structural integrity of the pipe, the fourth parameter having been determined at a later time than the second parameter; and

using at least the difference between the second parameter and the fourth parameter, calculate a degradation rate of the pipe.

46. The system according to claim 45:

the pipe being prestressed concrete cylinder pipe;

the second parameter comprising at least a quantity of broken wires; and

the processor being configured to use the degradation rate of the pipe to calculate when the pipe should be repaired or replaced.

47. The system according to claim 43, said system recommending pipe management action selected from the group consisting of repairing, replacing, and monitoring the pipe.

48. The system according to claim 43, the second parameter comprising at least results of eddy current inspection.

49. The system according to claim 43, the relation having at least a plurality of zones of risk.