FIELD OF THE DISCLOSURE

The present invention generally relates to liquid or gas transportation pipelines, and more particularly relates to a system and method for determining a range of possible locations of a leak in a pipeline. More particularly still, the present disclosure relates to a system and method for determining a range of possible locations of a leak in a pipeline with corresponding probabilities.

DESCRIPTION OF BACKGROUND

Pipelines are used to transport materials, such as gas, oil and water. A pipeline includes a plurality of connected pipe segments. Valves are oftentimes deployed along a pipeline to manage the flow of the materials running through the pipeline. Damage to a pipe segment, can cause a leak, which may be very detrimental to the environment, surrounding properties, and human beings since the flowing mass can be flammable or toxic. A leak also leads to significant economic loss.

To improve the transmission efficiency, compressor stations are oftentimes deployed along a pipeline. The compressor/pump stations pressurize the liquid (such as oil, water, liquid chemicals, etc.) or gas materials (collectively referred to herein as flowing materials) to increase the flow. The increased pressure imparts considerable kinetic energy to the moving mass within the pipeline. With even a small leak in the pipeline, the high pressure would make the leak significantly more detrimental to the environment, surrounding properties, and human beings. The high pressure would also cause significantly more economic loss.

The transmission pipelines are usually buried underground and exposed to corrosion by water and other materials. When installed above the ground, the pipelines are still exposed to the risk of damages by the natural events, human activities, corrosion by rainwater and moisture, and other factors. Pipelines are thus coated with external insulation. However, the insulation layer sometimes is compromised for various reasons. A breach to the insulation layer exposes a metal pipe segment to metallic corrosion. In addition, pipe segments are also gradually weakened by internal corrosion from active electrolytes in the flowing mass.

It is desirable to reduce the impact of any leak by prompt detection of the leak, determine the characteristics of the leak, such as the time of the leak, the location of the leak, etc. Certain methods have been proposed for detecting pipeline leaks. However, the conventional methods are not desirable for different reasons. For example, they rely upon pressure differential tests using Supervisory Control and Data Acquisition (“SCADA”) or Highway Addressable Remote Transducer (“HART”) industrial communication protocol-based pressure and velocity monitors that provide limited data obtained at slow time intervals. Though the conventional method provides a limited solution to situations with slowly changing pressure, they are not adequate to process, or even detect faster transient pressure waves generated by abrupt leaks to pipelines. Typically, the pressure drop due to a leak lasts less than 0.1 second. A data acquisition system with a sampling rate less than 60 Hz, or 60 samples per second, would not provide sufficient information to characterize the changing pressure.

The conventional methods can also rely on wavelet transformation. These conventional methods endeavored to identify a specific location of the leak. However, due to inaccuracy in the signal detection and the leak location estimation methods, the identified leak location is oftentimes not accurate. The wrong localization of the leak in a pipeline further delays any remedies to the leak.

A prompt and accurate determination of the location of the actual leak is thus highly desirable. Accordingly, there is a need for new and improved system and method for detecting remote pipeline leaks. It is desirable for the system and method to identify a range of possible locations of the leak and associate a probability with each subrange within the range. In addition, the new system and method needs to capture pipeline pressure data at high sampling rate to detect leaks in pipelines with fast changing pressure. Dynamic and static leak detection methods are further desired. The new system and the new methods are also desired to detect leaks on other types of metallic structures.

OBJECTS OF THE DISCLOSED SYSTEM, METHOD, AND APPARATUS

Accordingly, an objective of this disclosure is to provide a new system and method for detecting a leak in remote pipelines.

Another object of this disclosure is to provide a new system and a new method for localizing a leak in a remote pipeline by identifying a range of possible locations of the leak.

Another object of this disclosure is to provide a new system and a new method for localizing a leak in a remote pipeline by identifying a range of possible locations of the leak and assigning a probability for each subrange of locations within the range.

Another object of this disclosure is to provide a new system and a new method for detecting fault conditions in remote pipelines.

Another object of this disclosure is to provide a system and a method for detecting remote pipeline leaks by capturing pressure data at rates in excess of one-hundred (100) samples per second.

Another object of this disclosure is to provide a system and a method for detecting remote pipeline leaks by capturing pressure data at rates in excess of three-hundred (300) samples per second.

Another object of this disclosure is to provide a system and a method for detecting remote pipeline leaks by deriving the static and dynamic waveforms from the turbulent flow patterns within pipelines.

Another object of this disclosure is to provide a system and a method for detecting remote pipeline leaks by acquiring additional time stamped data from multiple valve openings and closures along a pipeline in addition to changes in data due to changes in compressor/pump output and flow data.

Another object of this disclosure is to provide a system and a method for detecting remote pipeline leaks by establishing normal operation patterns to form a baseline normal status of operation.

Another object of this disclosure is to provide a system and a method for protecting pipelines by determining aberrations in a normal flow pattern and transmitting it to a central station for alerting various parties and systems.

Another object of this disclosure is to provide a system and a method for detecting remote pipeline leaks by pressurizing a segment of pipeline between two valve stations with an incompressible fluid to localizing a leak based on pressure monitored at the valve stations.

Other advantages of this disclosure will be clear to a person of ordinary skill in the art. It should be understood, however, that a system, an apparatus or a method could practice the disclosure while not achieving all of the enumerated advantages, and that the protected disclosure is defined by the claims.

SUMMARY OF THE DISCLOSURE

Generally speaking, pursuant to the various embodiments, the present disclosure provides a leak detection and determination system. The leak detection system includes a set of monitoring devices installed on segments of a pipeline. The monitoring devices each include a set of sensors for reading time-varying signals of the pipeline. The signals can be pressure, temperature, velocity, etc. The monitoring devices each further include a microprocessor and a wireless network interface or a wired network interface for sending the collected field data (including the time-varying signals and corresponding timestamps) to a server computer system of the leak determination system over a wide area network, such as the Internet. The server computer system includes a processing unit, a memory operatively coupled to the processing unit, a networking interface operatively coupled to the processing unit, an operating system running on the processing unit, and a specialized server software application running on the operating system.

The specialized server software application retrieves and analyzes the field data using regression analysis to determine that a leak at a particular pipeline segment has occurred. The regression analysis derives a range of possible leak locations by estimating the arrival times of the negative pressure wave (NPW) to the monitoring devices installed at opposite ends of each pipeline segment. The specialized server software application further determines a probability distribution corresponding to subranges of the range of possible leak locations. The specialized server software application provides the range of possible leak locations and the probability distribution to client computer system for notifying a pipeline maintenance crew.

