The present disclosure relates generally to detecting a blockage in a pipeline for transporting hydrocarbon fluids. More particularly, the present disclosure relates to a system that that can remotely locate a blockage, such as a pipeline inspection gauge, without the need for a device located along the pipeline to provide position information.
Pipeline networks can be used for transporting oil and gas from their source to refineries, and from refineries to distribution centers. Maintenance of these pipeline networks can be performed for economic purposes as well as for regulatory purposes. Pigging (or the use of a pipeline inspection gauge, sometimes called a pig) can be employed in this maintenance. Maintenance can include both identifying and fixing pipeline problems. Examples of such problems include cracks, leaks, and internal debris that builds up over time.
Some newer pipeline inspection gauges are equipped with traction wheels, for example, and onboard circuitry, either mechanical or electrical, to keep track of the distance traveled by the pipeline inspection gauge. This information is then suitably telemetered to a monitoring system so that an operator can know the location of the pipeline inspection gauge throughout the time it is in the pipe.
Certain aspects and features relate to using dynamic pressure wave propagation in pipelines to interrogate and provide information about the available, unobstructed hydraulic diameter and any partial or complete blockages in the pipeline. Certain aspects and features can be used to locate a pipeline inspection gauge, which may be referred to herein as a pig. In terms of a pressure profile, the pig can be similar to other types of pipeline blockages.
A challenge is faced by pipeline operators is terms of the need to track pigs in real time, or near real time. Some newer pigs are equipped with traction wheels, for example, and onboard circuitry (either mechanical or electrical) to keep track of the distance traveled using the traction wheels. However, the majority of pigs still in use do not have such “smart” capabilities. Also, a smart pig's traction wheels can become fouled so that the telemetry coming from the smart pig is inaccurate. Additionally, the battery within a smart pig may become exhausted during use, meaning the pig must be located without relying on telemetry.
Certain aspects and features allow for tracking a blockage without the need for an instrument at or near the location of the blockage. The blockage reflects pressure signals and can be tracked using reflected pressure signals. There is no need to lay down cabling or instrumentation along a pipeline such as fiber optic cables or acoustic sensor cables. Instead, a pressure transducer in an existing port in the pipeline can be used. There is no need for the pipeline operator to turn off flow since the technique can make use of fluid flow that occurs during normal pipeline operations to generate dynamic pressure waves. The technique can be used at little cost and with little disruption to pipeline operations.
In one example, there is a pig in a pipeline and a pressure wave can be used to locate the pig. Regular pulsing of the pipeline with a pressure wave can further be used to locate the pig as it moves overtime. A valve or any other suitable device can be used to generate the pressure wave. Suitable devices for generating the pressure wave include a plunger and a pump. The pressure wave can also be generated with an acoustic transducer. A blockage detection algorithm can be used for location determination.
In some examples, a system using dynamic pressure wave propagation to locate a blockage in a pipeline includes a pressure transducer for coupling with a pipeline and a processing device communicatively that can be coupled to the pressure transducer. The system according to some examples further includes a non-transitory memory device including instructions that are executable by the processing device to cause the processing device to perform operations. In some examples, the operations include recording pressure as a function of time in response a dynamic pressure change in the pipeline to produce a pressure waveform and performing a time series analysis of the pressure waveform. The system can then determine a position of the blockage in the pipeline based on the time series analysis, and store or report the position of the blockage.
In some examples, the system can automatically launch a pig and provide real-time tracking by repeatedly determining, and storing or reporting, the position of the pig over time. The system can initiate the dynamic pressure change by operating a valve or valves, operating an air gun, operating a plunger, operating a pump, operating acoustic transducer, or operating a combination of these.
In some examples, the time series analysis of the pressure waveform includes segmenting an initial pressure value from a time series of pressure corresponding to the pressure waveform to form a wavelet, correlating the wavelet with the remainder of the time series of pressure, and removing correlation values below a pre-established threshold. The time series analysis can include performing a cross-correlation calculation for the pressure waveform to detect a delay value indicative of a reflection distance between the blockage and the source location. In some examples, the time series analysis includes applying a Fourier transform to the pressure waveform to provide low frequency components and calculating a time delay from the at least one low-frequency components.
These illustrative examples are given to introduce the reader to the general subject matter discussed here and are not intended to limit the scope of the disclosed concepts. The following sections describe various additional features and examples with reference to the drawings in which like numerals indicate like elements, and directional descriptions are used to describe the illustrative aspects but, like the illustrative aspects, should not be used to limit the present disclosure.
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The system 200 includes the computing device 140. The computing device 140 can include a processor 204, a memory 207, and a bus 206. The processor 204 can execute one or more operations for obtaining pressure transducer 109 and determining a location of a pig or other blockage. The processor 204 can execute instructions stored in the memory 207 to perform the operations. The processor 204 can include one processing device or multiple processing devices. Non-limiting examples of the processor 204 include a Field-Programmable Gate Array (“FPGA”), an application-specific integrated circuit (“ASIC”), a microprocessor, etc.
The processor 204 can be communicatively coupled to the memory 207 via the bus 206. The non-volatile memory 207 may include any type of memory device that retains stored information when powered off. Non-limiting examples of the memory 207 include electrically erasable and programmable read-only memory (“EEPROM”), flash memory, or any other type of non-volatile memory. In some examples, at least part of the memory 207 can include a medium from which the processor 204 can read instructions. A non-transitory computer-readable medium can include electronic, optical, magnetic, or other storage devices capable of providing the processor 204 with computer-readable instructions or other program code. Non-limiting examples of a computer-readable medium include (but are not limited to) magnetic disk(s), memory chip(s), ROM, random-access memory (“RAM”), an ASIC, a configured processor, optical storage, or any other medium from which a computer processor can read instructions. The instructions can include processor-specific instructions generated by a compiler or an interpreter from code written in any suitable computer-programming language, including, for example, C, C++, C#, etc.
In some examples, the memory 207 can include computer program code instructions 210 for initiating a pressure wave and determining the location of blockages using dynamic pressure wave propagation. Pressure waveforms 222 captured using pressure transducer 109 can be stored in memory 207 for analysis by processor 204 executing computer program code instructions 210. The system 200 can include a power source 220. The power source 220 can be in electrical communication with the computing device 140 and the communication device 144. In some examples, the power source 220 can include a battery or an electrical cable (e.g., a wireline). In some examples, the power source 220 can include an AC signal generator. The computing device 140 can operate the power source 220 to apply a signal to the communication device 144 to transmit location information or pressure waveforms. For example, the computing device 140 can cause the power source 220 to apply a voltage with a frequency within a specific frequency range to the communication device 144. In other examples, the computing device 140, rather than the power source 220, can apply the signal to communication device 144.
The communication device 144 of
System 200 in this example also includes input/output interface 232. Input/output interface 232 can connect to a keyboard, pointing device, display, and other computer input/output devices. An operator may provide input using the input/output interface 232. Such input may include a command to launch a pig or to initiate a pressure wave. Input/output interface 232 can also be used to display position information, pressure readings, or pressure waveforms locally to an operator using a display device (not shown.)
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When a pressure wave is launched, due to a valve operation for example, the wave travels down the pipe and reflects from any anomalies in the pipe. These anomalies include changes to the (inner) diameter or fluid properties, such as density, as well as from blockages in the pipeline. The hydrodynamics pressure is recorded as a function of time. By computing the time taken for the reflection from a blockage to arrive at the known pressure transducer location, the distance to the blockage is computed using the sound speed of the fluid in the pipe. In a particular example, by partially closing mainline trap valve 102, a sudden drop in pressure is created as the flow of material is restricted. When the valve is opened again, the pressure increases, returning to the original value. This creates a negative pressure wave. A representation of this wave and typical pressure time series is shown in graph 500 of
There are several techniques to compute the two-way travel time from the type of signal shown in
Cross-correlation of the signal can be determined by performing a cross-correlation of the pressure time signal. When cross-correlation is performed, repeated structures in the time series, such as reflections from blockages, show up as different delay values. An example of the correlation result is shown in graph 600 of
Frequency analysis is performed by applying a Fourier transform to the pressure waveform. Repetitions of the source signal due to multiple reflections between the source and the blockage show up as low-frequency components in the spectrum. Tracking these components allows for the calculation of the time delay associated with the blockage signal. Time delay is calculated from a low-frequency component and indicates transit time, which is indicative of the reflection distance between the blockage and the pressure wave source location.
Terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” or “comprising,” when used in this specification, specify the presence of stated features, steps, operations, elements, or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, or groups thereof. Additionally, comparative, quantitative terms such as “above,” “beneath,” “less,” and “greater” are intended to encompass the concept of equality, thus, “less” can mean not only “less” in the strictest mathematical sense, but also, “less than or equal to.”
Unless specifically stated otherwise, it is appreciated that throughout this specification that terms such as “processing,” “calculating,” “determining,” “operations,” or the like refer to actions or processes of a computing device, such as the controller or processing device described herein, that can manipulate or transform data represented as physical electronic or magnetic quantities within memories, registers, or other information storage devices, transmission devices, or display devices. The order of the process blocks presented in the examples above can be varied, for example, blocks can be re-ordered, combined, or broken into sub-blocks. Certain blocks or processes can be performed in parallel. The use of “configured to” herein is meant as open and inclusive language that does not foreclose devices configured to perform additional tasks or steps. Additionally, the use of “based on” is meant to be open and inclusive, in that a process, step, calculation, or other action “based on” one or more recited conditions or values may, in practice, be based on additional conditions or values beyond those recited. Elements that are described as “connected,” “connectable,” or with similar terms can be connected directly or through intervening elements.
In some aspects, a system for monitoring drill cuttings is provided according to one or more of the following examples. As used below, any reference to a series of examples is to be understood as a reference to each of those examples disjunctively (e.g., “Examples 1-4” is to be understood as “Examples 1, 2, 3, or 4”).
Example 1. A system includes a pressure transducer for coupling with a pipeline for transporting hydrocarbon fluids, and a processing device communicatively couplable to the pressure transducer, and a non-transitory memory device. The memory device includes instructions that are executable by the processing device to cause the processing device to perform operations. The operations include recording pressure as a function of time in response a dynamic pressure change in the pipeline to produce a pressure waveform, performing a time series analysis of the pressure waveform, determining a position of a blockage in the pipeline based on the time series analysis, and storing or reporting the position of the blockage in the pipeline.
Example 2. The system of example 1, wherein the operations further include launching a pipeline inspection gauge; and repeatedly determining and storing or reporting the position of the pipeline inspection gauge over time.
Example 3. The system of example(s) 1-2 wherein storing or reporting the position of the blockage further includes reporting the position of the blockage to a remote location using wireless communication.
Example 4. The system of example(s) 1-3 wherein the operations further include initiating the dynamic pressure change by operating a valve, an air gun, a plunger, a pump, an acoustic transducer or any combination of these at a source location.
Example 5. The system of example(s) 1-4 wherein performing the time series analysis further includes segmenting an initial pressure value from a time series of pressure corresponding to the pressure waveform to form a wavelet, correlating the wavelet with a remainder of the time series of pressure, and removing correlation values below a pre-established threshold, wherein at least one of any remaining correlation values is indicative of a reflection distance between the blockage and the source location.
Example 6. The system of example(s) 1-5 wherein performing the time series analysis further includes performing a cross-correlation calculation for the pressure waveform to a detect delay value indicative of a reflection distance between the blockage and the source location.
Example 7. The system of example(s) 1-6 wherein performing the time series analysis further includes applying a Fourier transform to the pressure waveform to produce at least one low-frequency component, and calculating a time delay from the at least one low-frequency component, the time delay indicative of a reflection distance between the blockage and the source location.
Example 8. A method includes recording, by a processor, pressure as a function of time in response a dynamic pressure change in a pipeline to produce a pressure waveform, the pipeline transporting hydrocarbon fluids, performing, by the processor, a time series analysis of the pressure waveform, determining, by the processor, a position of a blockage in the pipeline based on the time series analysis, and storing or reporting, by the processor, the position of the blockage in the pipeline.
Example 9. The method of example 8 further includes launching a pipeline inspection gauge, and repeatedly determining and storing or reporting the position of the pipeline inspection gauge over time.
Example 10. The method of example(s) 8-9 further includes initiating the dynamic pressure change by operating a valve, an air gun, a plunger, a pump, an acoustic transducer or any combination of these at a source location.
Example 11. The method of example(s) 8-10 wherein performing the time series analysis further includes segmenting an initial pressure value from a time series of pressure corresponding to the pressure waveform to form a wavelet, correlating the wavelet with a remainder of the time series of pressure, and removing correlation values below a pre-established threshold, wherein at least one of any remaining correlation values is indicative of a reflection distance between the blockage and the source location.
Example 12. The method of example(s) 8-11 wherein performing the time series analysis further includes performing a cross-correlation calculation for the pressure waveform to a detect delay value indicative of a reflection distance between the blockage and the source location.
Example 13. The method of example(s) 8-12 wherein performing the time series analysis further includes applying a Fourier transform to the pressure waveform to produce at least one low-frequency component, and calculating a time delay from the at least one low-frequency component, the time delay indicative of a reflection distance between the blockage and the source location.
Example 14. A non-transitory computer-readable medium that includes instructions that are executable by a processor for causing the processor to perform operations related to monitoring a location of a blockage in a pipeline for transporting hydrocarbon fluids. The operations include recording pressure as a function of time in response a dynamic pressure change in the pipeline to produce a pressure waveform, performing a time series analysis of the pressure waveform, determining a position of the blockage in the pipeline based on the time series analysis, and storing or reporting the position of the blockage in the pipeline.
Example 15. The non-transitory computer-readable medium of example 14, wherein the operations further include launching a pipeline inspection gauge, and repeatedly determining and storing or reporting the position of the pipeline inspection gauge over time.
Example 16. The non-transitory computer-readable medium of example(s) 14-15 wherein storing or reporting the position of the blockage further includes reporting the position of the blockage to a remote location using wireless communication.
Example 17. The non-transitory computer-readable medium of example(s) 14-16 wherein the operations further comprise initiating the dynamic pressure change by operating a valve, an air gun, a plunger, a pump, an acoustic transducer, or any combination of these at a source location.
Example 18. The non-transitory computer-readable medium of example(s) 14-17 wherein performing the time series analysis further includes segmenting an initial pressure value from a time series of pressure corresponding to the pressure waveform to form a wavelet, correlating the wavelet with a remainder of the time series of pressure, and removing correlation values below a pre-established threshold, wherein at least one of any remaining correlation values is indicative of a reflection distance between the blockage and the source location.
Example 19. The non-transitory computer-readable medium of example(s) 14-18 wherein performing the time series analysis further includes performing a cross-correlation calculation for the pressure waveform to a detect delay value indicative of a reflection distance between the blockage and the source location.
Example 20. The non-transitory computer-readable medium of example(s) 14-19 wherein performing the time series analysis further includes applying a Fourier transform to the pressure waveform to produce at least one low-frequency component, and calculating a time delay from the at least one low-frequency component, the time delay indicative of a reflection distance between the blockage and the source location.
The foregoing description of the examples, including illustrated examples, has been presented only for the purpose of illustration and description and is not intended to be exhaustive or to limit the subject matter to the precise forms disclosed. Numerous modifications, combinations, adaptations, uses, and installations thereof can be apparent to those skilled in the art without departing from the scope of this disclosure. The illustrative examples described above are given to introduce the reader to the general subject matter discussed here and are not intended to limit the scope of the disclosed concepts.
Filing Document | Filing Date | Country | Kind |
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PCT/US2019/041179 | 7/10/2019 | WO | 00 |
Number | Date | Country | |
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62800970 | Feb 2019 | US |