Method and apparatus for detecting and isolating a rupture in fluid distribution system

• US 6,535,827 B1
• Filed: 10/30/2000
• Issued: 03/18/2003
• Est. Priority Date: 10/28/1999
• Status: Active Grant

• Current Assignee: MPR Associates, Inc. (Research Triangle Institute)
• Original Assignee: MPR Associates, Inc. (Research Triangle Institute)
• Inventors: Runnerstrom, Eric, Bradley, Melissa, Downs, Ryan, Lestina, Thomas
• Primary Examiner(s): Nghiem, Michael
• Assistant Examiner(s): VO, HIEN XUAN
• Application Number:
  US09/698,484
• Time in Patent Office: 869 Days
• Field of Search: 702/51, 702/50, 702/100, 137/498, 137/67, 137/312, 137/613, 137/68.19, 137/486, 137/495, 137/624.12, 137/487.5, 735/21
• US Class Current: 702/51
• CPC Class Codes: F17D 5/02 Preventing, monitoring, or locating loss
• CPC Class Codes: G01F 25/00 Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume
• CPC Class Codes: G01M 3/2807 for pipes G01M3/2892, G01M3/30 take precedence
• CPC Class Codes: G01M 3/2815 using pressure measurements
• CPC Class Codes: Y10T 137/7759 Responsive to change in rate of fluid flow
• CPC Class Codes: Y10T 137/7782 With manual or external control for line valve
• CPC Class Codes: Y10T 137/86397 With independent valve controller

Abstract

Rupture path logic methods of detecting, locating and isolating ruptures within a fluid piping system are disclosed, wherein a rupture within a piping system can be detected and isolated based solely upon local pressure and flow rate measurements at individual valves within the system without the need for communication of measured fluid data between valves at various locations throughout the system. A fluid characteristic is determined individually for each valve based upon the pressure and flow rate measurements at the valve, and that fluid characteristic is compared with set point fluid characteristic information to determine whether each valve is on a fluid path between a fluid supply source and a rupture. Upon detecting a rupture, valves detected as being on such a fluid path are automatically closed within the system in an order of valves furthest from all online fluid supply sources closing first, thereby ensuring eventual isolation of the rupture while allowing intact sections of the piping system to remain open and operational. An automatic rupture detection and isolation fluid piping system is also disclosed that utilizes rupture path logic methods to isolate detected ruptures within the system.

Claims

1. A method of detecting and isolating ruptures within a fluid piping system having at least one fluid supply source delivering fluid into and through said system and a plurality of open valves, said method comprising:

(a) continuously measuring a fluid characteristic at or near each valve;

(b) continuously detecting whether each valve within said system is on a rupture path within said system by comparing, for each valve, the fluid characteristic measured for the valve with a set point fluid characteristic for the valve;

(c) closing at least one valve detected in step (b) as being on said rupture path; and

(d) allowing one or more of the valves not detected in step (b) as being on said rupture path to remain open.

2. The method of claim 1, wherein step (c) includes closing a plurality of valves detected as being on said rupture path in an order such that a valve detected as being on said rupture path and furthest from said at least one fluid supply source is closed prior to closure of a valve detected as being on said rupture path and closer to said at least one fluid supply source.

3. A method of detecting and isolating ruptures within a fluid piping system having at least one fluid supply source delivering fluid into and through said system and a plurality of open valves, said method comprising:

(a) measuring a fluid characteristic at or near each valve;

(b) detecting whether each valve is on a rupture path within said system by comparing, for each valve, the fluid characteristic measured for the valve with a set point fluid characteristic for the valve;

(c) closing at least one valve detected in step (b) as being on said rupture path and being further in distance from said at least one fluid supply source than all other valves detected in step (b) as being on said rupture path; and

(d) repeating steps (a)-(c) until all valves detected in step (b) as being on said rupture path are closed in step (c) thereby isolating said rupture path within said system from said at least one fluid supply source.

4. The method of claim 3, wherein step (a) includes measuring a downstream pressure and a flow rate for each valve, and step (b) includes comparing, for each valve, the measured downstream pressure and flow rate for the valve with a set point pressure and a set point flow rate for the valve and detecting a valve as being on a rupture path when its measured downstream pressure is less than its set point pressure and its measured flow rate is greater than its set point flow rate.

5. The method of claim 3, wherein step (a) includes measuring a rupture resistance for each valve, and step (b) includes comparing, for each valve, the measured rupture resistance for the valve with a set point rupture resistance for the valve and detecting a valve as being on a rupture path when its rupture resistance is less than its set point rupture resistance.

6. The method of claim 3, wherein step (c) includes:

(c1) initiating a timer for said at least one valve detected as being on said rupture path that records a rupture time at which a rupture is first detected;

(c2) calculating a time delay for said at least one valve detected as being on said rupture path; and

(c3) closing said at least one valve detected as being on said rupture path when said rupture time exceeds said time delay.

7. The method of claim 6, wherein step (c2) includes calculating a time delay that is proportional to a distance between said at least one valve and said at least one fluid supply source.

10. The method of claim 3, further comprising, subsequent to step (c):

(e) measuring a fluid characteristic at or near each closed valve;

(f) detecting whether each closed valve within said system is still on said rupture path within said system by comparing, for each closed valve, the fluid characteristic measured at or near the closed valve with a set point fluid characteristic for the closed valve; and

(g) opening at least one closed valve detected in step (f) as no longer being on said rupture path.

11. The method of claim 3, further comprising independently conducting steps (a)-(c) at each valve utilizing a processor of each valve.

12. The method of claim 11, further comprising:

(e) providing set point fluid characteristic information to each processor from a remote master controller.

8. A method of detecting and isolating ruptures within a fluid piping system having at least one fluid supply source delivering fluid into and through said system and a plurality of open valves, said method comprising:

(a) measuring a fluid characteristic at or near each valve;

(b) detecting whether each valve is on a rupture path within said system based upon a comparison of said fluid characteristic measured at each valve with a set point fluid characteristic for each valve;

(c) closing at least one valve detected in step (b) as being on said rupture path and being further in distance from said at least one fluid supply source than all other valves detected in step (b) as being on said rupture path; and

(d) repeating steps (a)-(c) until all valves detected in step (b) as being on said rupture path are closed in step (c) thereby isolating said rupture path within said system from said at least one fluid supply source;

wherein step (c) includes

(c1) initiating a timer for said at least one valve detected as being on said rupture path that records a rupture time at which a rupture is first detected;

(c2) calculating a time delay for said at least one valve detected as being on said rupture path, said step of calculating including calculating a time delay that is proportional to a distance between said at least one valve and said at least one fluid supply source, said step of calculating further including calculating said time delay as a function of a least number of valves in said system separating said at least one valve and said at least one fluid supply source, said step of calculating including determining said least number of valves by summing a total number of valves between said at least one valve and said at least one fluid supply source in a direction opposite a direction of fluid flow through said at least one valve; and

(c3) closing said at least one valve detected as being on said rupture path when said rupture time exceeds said time delay.

9. The method of claim 8, wherein step (a) includes:

(a1) measuring an upstream pressure and a downstream pressure at or near said at least one valve so as to establish the direction of fluid flow through said at least one valve prior to step (c2).

13. A method for controlling a valve in a fluid piping system having at least one fluid supply source delivering fluid into and through said system, said method comprising:

(a) continuously measuring a fluid characteristic at or near said valve to obtain a value for the fluid characteristic;

(b) continuously detecting whether said valve is on a rupture path within said system by comparing the value for the measured fluid characteristic with a set point value for the fluid characteristic for said valve; and

(c) opening or closing said valve based upon a detection in step (b) of said valve being on said rupture path, wherein said valve closes or remains closed if said detection indicates that said valve is on said rupture path, and said valve opens or remains open if said detection does not indicate that said valve is on said rupture path.

14. The method of claim 13, wherein step (a) includes measuring a downstream pressure and a flow rate, and step (b) includes comparing the measured downstream pressure and flow rate with a set point pressure and a set point flow rate, and detecting said valve as being on said rupture path when said measured downstream pressure is less than said set point pressure and said measured flow rate is greater than said set point flow rate.

15. The method of claim 13, wherein step (a) includes measuring a rupture resistance, and step (b) includes comparing the measured rupture resistance with a set point rupture resistance and detecting said valve as being on said rupture path when said measured rupture resistance is less than said set point rupture resistance.

16. The method of claim 13, wherein step (b) includes:

(b1) initiating a timer when said valve is detected as being on said rupture path that records a rupture time at which a rupture is first detected;

and step (c) includes;

(c1) calculating a time delay for closing said valve when said valve is detected as being on said rupture path; and

c2) closing said valve when said rupture time exceeds said time delay.

17. The method of claim 16, wherein step (c1) includes calculating a time delay that is proportional to a distance between said valve and said at least one fluid supply source.

20. The method of claim 13, wherein steps (a)-(c) are performed using a processor of said valve that stores set point fluid characteristic information for said valve.

21. The method of claim 20, further comprising:

(e) providing said set point fluid characteristic information to said processor from a remote master controller.

18. A method for controlling a valve in a fluid piping system having at least one fluid supply source delivering fluid into and through said system, said method comprising:

(a) continuously measuring a fluid characteristic at or near said valve;

(b) continuously detecting whether said valve is on a rupture path within said system by comparing said measured fluid characteristic with a set point fluid characteristic for said valve; and

(c) opening or closing said valve based upon a detection in step (b) of said valve being on said rupture path, wherein said valve closes or remains closed if said detection indicates that said valve is on said rupture path, and said valve opens or remains open if said detection does not indicate that said valve is on said rupture path;

wherein step (b) includes;

(b1) initiating a timer when said valve is detected as being on said rupture path that records a rupture time at which a rupture is first detected;

wherein step (c) includes;

(c1) calculating a time delay for closing said valve when said valve is detected as being on said rupture path, said step of calculating including calculating a time delay that is proportional to a distance between said valve and said at least one fluid supply source, wherein said system includes a plurality of valves and said step of calculating further includes calculating said time delay as a function of a least number of valves in said system separating said valve detected as being on said rupture path and said at least one fluid supply source, said step of calculating including determining said least number of valves by summing a total number of valves between said valve detected as being on said rupture path and said at least one fluid supply source in a direction opposite a direction of fluid flow through said valve detected as being on said rupture path; and

(c2) closing said valve when said rupture time exceeds said time delay.

19. The method of claim 18, wherein step (a) includes:

(a1) measuring an upstream pressure and a downstream pressure at or near said valve detected as being on said rupture path so as to establish the direction of fluid flow through said valve detected as being on said rupture path prior to calculating said time delay in step (c1).

22. A fluid piping system capable of automatic detection and isolation of ruptures, said system comprising:

at least one fluid supply source delivering fluid into and through said system; and

at least one valve including a valve inlet, a valve outlet, a first pressure sensor at or near said valve inlet, a second pressure sensor at or near said valve outlet, an actuator configured to automatically open and close said at least one valve, and a processor in communication with said pressure sensors;

wherein

said processor is configured to measure a fluid characteristic at or near said at least one valve based upon pressure values measured by said pressure sensors, to detect whether said at least one valve is on a rupture path within said system by comparing the measured fluid characteristic with a set point fluid characteristic, and to open or close said at least one valve via said actuator based upon a determination by said processor as to whether said at least one valve is on said rupture path.

23. The system of claim 22, wherein said system includes a plurality of said valves having corresponding processors configured to respectively open or close said valves independent of all other of said valves in said system.

24. The system of claim 22, wherein said processor includes a timer that is configured to activate and record a rupture time upon the determination that said at least one valve is on said rupture path, and said processor is configured to close said at least one valve when said rupture time for said at least one valve exceeds a predetermined time delay for said at least one valve.

25. The system of claim 24, wherein said predetermined time delay for said at least one valve is proportional to a distance between said at least one valve and said at least one fluid supply source, such that said time delay decreases as the distance between said at least one valve and said at least one fluid supply source increases.

26. The system of claim 22, wherein said at least one valve includes a flow rate sensor at or near said valve inlet or said valve outlet, and said processor is further configured to obtain flow rate measurements from said flow rate sensor.

27. The system of claim 22, wherein said processor is further configured to store set point fluid characteristic information for said at least one valve, and said processor includes a transceiver configured to receive set point fluid characteristic information from a remote master controller and to communicate with said at least one fluid supply source.