A wireless early warning monitoring method for ocean oil and gas pipelines

Abstract

The application provides a kind of marine oil and gas pipeline wireless early warning monitoring method, utilizes stress sensor, angle sensor, vibration sensor and flow rate sensor to collect the state data of marine oil and gas pipeline, real-time fatigue state analysis is carried out through fusion algorithm, once fatigue damage occurs, immediately transmit early warning signal to sea surface monitoring platform through wireless acoustic communication, realize real-time safety warning, realize the safety warning of marine oil and gas pipeline, can effectively monitor the integrity and safety of marine oil and gas pipeline, the application adopts wireless transmission, easy to deploy, can effectively monitor the fatigue state parameters of marine oil and gas pipeline and carry out real-time early warning, can effectively make up the problem of small monitoring range and real-time, can be widely applied in the field of marine oil and gas pipeline safety monitoring.

Description

Technical Field

[0001] This invention relates to the field of underwater signal processing, and to theories related to safety early warning monitoring, acoustic signal processing, and wireless communication. Background Technology

[0002] With increasingly stringent safety and environmental protection requirements for offshore oil and gas exploration and development, and the continuous expansion of oilfield exploration and development areas, the demands for the accuracy and reliability of offshore oil and gas pipeline integrity assessments are also rising. Monitoring offshore oil and gas pipelines and managing and maintaining overhangs have become essential requirements. Offshore oil and gas pipelines are a crucial component of offshore oil and gas gathering, transportation, and storage systems, often referred to as the lifeline of offshore oil. In the harsh marine environment, they are prone to fatigue failure and other accidents, leading to huge economic losses and severe ecological disasters. Monitoring offshore oil and gas pipelines is the prerequisite and foundation for scientifically analyzing their stability and assessing their fatigue life. It is a vital link in reducing failure risks, preventing accidents, and ensuring safe operation, and is of great significance to the safe operation of offshore oil and gas development.

[0003] Safety monitoring of offshore oil and gas pipelines is a crucial means of safeguarding the "lifeline" of offshore oil and gas development. Originating from the tragic accidents and profound lessons learned during their service life, it is a key link in integrity management and has a long history abroad. Researching key technologies for offshore pipeline safety monitoring is an essential step towards deep-water exploration and a necessary strategy for maintaining the safety and integrity of offshore oil and gas pipelines during service. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention provides a wireless early warning and monitoring method for marine oil and gas pipelines. This invention uses stress sensors, angle sensors, vibration sensors, and flow velocity sensors to collect status data of marine oil and gas pipelines. Through a fusion algorithm, it achieves safety early warning for marine oil and gas pipelines, effectively monitoring the integrity and safety of these pipelines, which is of great significance for ensuring the development of marine oil and gas resources.

[0005] To address the shortcomings of existing marine oil and gas pipeline monitoring methods, which primarily rely on wired monitoring or underwater robot inspections, such as high equipment and deployment costs, time-consuming and labor-intensive inspections, and a lack of real-time overall monitoring of marine oil and gas pipelines, this invention proposes a wireless early warning monitoring method for marine oil and gas pipelines. This method uses stress sensors, angle sensors, vibration sensors, and flow velocity sensors to collect state data of marine oil and gas pipelines. Real-time fatigue state analysis is performed through a fusion algorithm. Once fatigue damage is detected, an early warning signal is immediately transmitted to the surface monitoring platform via wireless acoustic communication, achieving real-time safety early warning.

[0006] To address the problems of existing marine oil and gas pipeline monitoring methods, which mainly rely on wired monitoring or underwater robot inspections, such as high equipment and deployment costs, time-consuming and labor-intensive inspections, and lack of real-time monitoring of the entire marine oil and gas pipeline, this invention proposes a wireless early warning monitoring method for marine oil and gas pipelines.

[0007] The steps of the technical solution adopted by the present invention to solve its technical problem are as follows:

[0008] Step 1: Underwater multi-sensor signal acquisition;

[0009] A wireless early warning monitoring device, comprising a force sensor, an angle sensor, a vibration sensor, and a flow velocity sensor, is installed on an offshore oil and gas pipeline. This device acquires data signals collected by the force sensor, angle sensor, vibration sensor, and flow velocity sensor respectively. These data signals correspond to the tension signal Z and the tilt angle signal, respectively. Vibration signal X and ocean current velocity signal Q;

[0010] Step 2: Signal preprocessing;

[0011] The signals received by the mechanical sensor, angle sensor, vibration sensor and flow velocity sensor are processed in a unified time and space manner through a clock synchronization method to achieve real-time synchronization of the signals collected by each sensor;

[0012] Step 3: Calculate the intrinsic frequencies of offshore oil and gas pipelines;

[0013] Based on the relevant parameters of the offshore oil and gas pipeline and the measured tension, the immediate intrinsic frequency of the pipeline is calculated. ;

[0014] Step 4: Eliminate the influence of gravitational acceleration;

[0015] Due to the dragging effect of ocean currents, offshore oil and gas pipelines may tilt, based on measured tilt angle signals. To remove the influence of gravitational acceleration, calculate the pipe vibration frequency after removing the influence of gravitational acceleration.

[0016] Step 5: Frequency detection of vibration signals in offshore oil and gas pipelines;

[0017] The frequency of the pipeline vibration signal was calculated using the Chirp-Z transform.

[0018] Step 6: Root mean square (RMS) detection of displacement in offshore oil and gas pipelines;

[0019] Calculate the displacement and root mean square displacement of offshore oil and gas pipelines respectively. ;

[0020] Step 7: Calculate the vortex shedding frequency;

[0021] Calculate the vortex shedding frequency f of offshore oil and gas pipeliness ;

[0022] Step 8: Assessment of fatigue warning status;

[0023] When the actual vibration frequency of the detected marine oil and gas pipeline In the middle, there are existing and pipeline eigenfrequency Similarly, it also has the frequency of vortex shedding in the pipeline. Same, and root mean square displacement Greater than the warning threshold At that time, it is determined that the pipeline has a fatigue warning;

[0024] Step 9: Real-time transmission of fatigue early warning information;

[0025] When a fatigue warning occurs in an offshore oil and gas pipeline, the fatigue warning information is wirelessly transmitted to the surface platform via a transducer. The fatigue warning information is the vibration frequency of the offshore oil and gas pipeline. and root mean square of pipe displacement This facilitates timely emergency response.

[0026] In the third step, the intrinsic frequency of the pipeline is immediately... for:

[0027] n=1,2……;

[0028] Where L is the length of the marine oil and gas pipeline, Z is the measured tension, E is the elastic modulus, I is the second moment of inertia, b is the dry mass per unit length of the pipeline (dry mass refers to the mass when not submerged in water), b1 is the additional mass per unit length (additional mass per unit length refers to the mass increase per meter after submersion in water), and n is the order (n=1,2,3…). There are n eigenfrequency numbers, representing eigenfrequency numbers of different orders.

[0029] In the fourth step, the pipe vibration frequency after removing the influence of gravitational acceleration is:

[0030] ;

[0031] Where X1 represents the pipeline vibration frequency after removing the influence of gravitational acceleration, and X represents the measured vibration signal of the offshore oil and gas pipeline. The measured pipe inclination angle is given, and g is taken as 9.8 m / s². 2 This is the acceleration due to gravity.

[0032] In the fifth step, the step of calculating the frequency of the pipeline vibration signal is as follows:

[0033] ;

[0034] X1 represents the pipe vibration frequency after removing the influence of gravitational acceleration. , , z is the independent variable after the Chirp-Z transform. and Let be any positive real number. The angle of the transformed circular frequency. and This is the starting point of the polar coordinates of the independent variable z in the Chirp-Z transform. is the imaginary part, e is the natural logarithm, M is the sampling length of the vibration signal X1, and m is the signal sequence.

[0035] In the sixth step, the displacement and root mean square of the offshore oil and gas pipeline are calculated respectively. The pipeline displacement is:

[0036] ;

[0037] in, , To obtain the vibration frequency The minimum value is the lower cutoff frequency. To obtain the vibration frequency The maximum value is the upper limit cutoff frequency. For frequency resolution, Let π be the mathematical constant, and K be the number of points in the Fourier transform.

[0038] The root mean square of the pipe displacement is:

[0039] .

[0040] In the seventh step, the vortex shedding frequency f of the offshore oil and gas pipeline... s for:

[0041] ;

[0042] Where Q is the measured ocean current velocity in m / s, D is the diameter of the ocean pipeline in m, and St is the Strouhal number, with a value of 0.21.

[0043] The warning threshold The value ranges from 0.8D to 1D.

[0044] The beneficial effects of this invention lie in proposing a wireless early warning monitoring method for marine oil and gas pipelines. This method utilizes stress sensors, angle sensors, vibration sensors, and flow velocity sensors to collect state data of marine oil and gas pipelines. Real-time fatigue state analysis is performed through a fusion algorithm. Once fatigue damage occurs, an early warning signal is immediately transmitted to a surface monitoring platform via wireless acoustic communication, achieving real-time safety early warning. This method employs wireless transmission, is easy to deploy, and can effectively monitor fatigue state parameters of marine oil and gas pipelines and provide real-time early warnings. Compared with existing wired monitoring methods or underwater robot inspections, it effectively overcomes the problems of limited monitoring range and real-time performance. It can be widely applied in the field of marine oil and gas pipeline safety monitoring, ensuring the safe operation of marine oil and gas resources and marine equipment in my country. Attached Figure Description

[0045] Figure 1 This is a flowchart of the overall method of the present invention. Detailed Implementation

[0046] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0047] Step 1: Underwater multi-sensor signal acquisition

[0048] Devices equipped with mechanical sensors, angle sensors, vibration sensors, and flow velocity sensors are installed on offshore oil and gas pipelines to collect corresponding data signals, which are categorized into tension signal Z and tilt angle signal Z. Vibration signal X, ocean current velocity signal Q.

[0049] Step 2: Signal Preprocessing

[0050] The signals received by each sensor are processed in a unified spatiotemporal manner to achieve real-time synchronization of the signals collected by each sensor.

[0051] Step 3: Calculate the intrinsic frequencies of offshore oil and gas pipelines

[0052] Based on the relevant parameters of the offshore oil and gas pipeline and the measured tension, the immediate intrinsic frequency of the pipeline is calculated.

[0053] ;

[0054] Where L is the length of the marine oil and gas pipeline, Z is the measured tension, E is the elastic modulus, I is the second moment of inertia, b is the dry mass per unit length of the pipeline, b1 is the additional mass per unit length, and n is the order, n=1,2,3…

[0055] Step 4: Eliminate the influence of gravitational acceleration

[0056] Due to the dragging effect of ocean currents, offshore oil and gas pipelines may tilt, based on measured tilt angle signals. Remove the influence of gravitational acceleration.

[0057] ;

[0058] Step 5: Frequency detection of vibration signals in offshore oil and gas pipelines

[0059] The frequency of the pipeline vibration signal was calculated using the Chirp-Z transform:

[0060] ;

[0061] in , , , and Let be any positive real number. The angle after transformation. and For two polar coordinates, is the imaginary part, and M is the number of Chirp-Z transform points.

[0062] Step 6: Root Mean Square Displacement Detection of Offshore Oil and Gas Pipelines

[0063] The displacement of offshore oil and gas pipelines is calculated as follows:

[0064] ;

[0065] in, , The lower cutoff frequency, The upper limit cutoff frequency, Frequency resolution;

[0066] Root mean square of pipe displacement for:

[0067] ;

[0068] Step 7: Calculate the vortex shedding frequency

[0069] Calculate the vortex shedding frequency of offshore oil and gas pipelines:

[0070] ;

[0071] Where Q is the measured ocean current velocity in m / s, D is the diameter of the ocean pipeline in m, and St is the Strouhal number, which is taken as 0.21 in engineering practice.

[0072] Step 8: Judging the fatigue warning status

[0073] When the actual vibration frequency of the detected marine oil and gas pipeline In the middle, there are existing and pipeline eigenfrequency Similarly, it also has the frequency of vortex shedding in the pipeline. Same, and root mean square displacement Greater than the warning threshold At that time, it is determined that the pipeline has a fatigue warning. The value ranges from 0.8D to 1D.

[0074] Step 9: Real-time transmission of fatigue early warning information

[0075] When an early warning is issued for an offshore oil and gas pipeline, the fatigue warning information of the pipeline can be transmitted to the surface platform in real time through wireless underwater acoustic communication technology, so as to facilitate timely emergency measures.

Claims

1. A wireless early warning monitoring method for marine oil and gas pipelines, characterized in that... Includes the following steps: Step 1: Underwater multi-sensor signal acquisition; A wireless early warning monitoring device, comprising a force sensor, an angle sensor, a vibration sensor, and a flow velocity sensor, is installed on an offshore oil and gas pipeline. This device acquires data signals collected by the force sensor, angle sensor, vibration sensor, and flow velocity sensor respectively. These data signals correspond to the tension signal Z and the tilt angle signal, respectively. Vibration signal X and ocean current velocity signal Q; Step 2: Signal preprocessing; The signals received by the mechanical sensor, angle sensor, vibration sensor and flow velocity sensor are processed in a unified time and space manner through a clock synchronization method to achieve real-time synchronization of the signals collected by each sensor; Step 3: Calculate the intrinsic frequencies of offshore oil and gas pipelines; Based on the relevant parameters of the offshore oil and gas pipeline and the measured tension, the immediate intrinsic frequency of the pipeline is calculated. ; Step 4: Eliminate the influence of gravitational acceleration; Due to the dragging effect of ocean currents, offshore oil and gas pipelines may tilt, based on measured tilt angle signals. To remove the influence of gravitational acceleration, calculate the pipe vibration frequency after removing the influence of gravitational acceleration. Step 5: Frequency detection of vibration signals in offshore oil and gas pipelines; The frequency of the pipeline vibration signal was calculated using the Chirp-Z transform. Step 6: Root mean square (RMS) detection of displacement in offshore oil and gas pipelines; Calculate the displacement and root mean square displacement of offshore oil and gas pipelines respectively. ; Step 7: Calculate the vortex shedding frequency; Calculate the vortex shedding frequency f of offshore oil and gas pipelines s ; Step 8: Assessment of fatigue warning status; When the actual vibration frequency of the detected marine oil and gas pipeline In the middle, there are existing and pipeline eigenfrequency Similarly, it also has the frequency of vortex shedding in the pipeline. The same, and the root mean square displacement Greater than the warning threshold At that time, it is determined that the pipeline has a fatigue warning; Step 9: Real-time transmission of fatigue early warning information; When a fatigue warning occurs in an offshore oil and gas pipeline, the fatigue warning information is wirelessly transmitted to the surface platform via a transducer. The fatigue warning information is the actual vibration frequency of the offshore oil and gas pipeline. and root mean square of pipe displacement This facilitates timely emergency response.

2. The wireless early warning monitoring method for marine oil and gas pipelines according to claim 1, characterized in that: In the third step, the intrinsic frequency of the pipeline is immediately... for: ，n=1,2……； Where L is the length of the marine oil and gas pipeline, Z is the measured tension, E is the elastic modulus, I is the second moment of inertia, b is the dry mass per unit length of the pipeline (dry mass refers to the mass when not submerged in water), b1 is the additional mass per unit length (additional mass per unit length refers to the mass increase per meter after submersion in water), and n is the order (n=1,2,3…). There are n eigenfrequency groups, representing eigenfrequency groups of different orders.

3. The wireless early warning monitoring method for marine oil and gas pipelines according to claim 1, characterized in that: In the fourth step, the pipe vibration frequency after removing the influence of gravitational acceleration is: ； Where X1 represents the pipeline vibration frequency after removing the influence of gravitational acceleration, and X represents the measured vibration signal of the offshore oil and gas pipeline. The measured pipe inclination angle is given, and g is taken as 9.8 m / s². 2 This is the acceleration due to gravity.

4. The wireless early warning monitoring method for marine oil and gas pipelines according to claim 1, characterized in that: In the fifth step, the step of calculating the frequency of the pipeline vibration signal is as follows: ； X1 represents the pipe vibration frequency after removing the influence of gravitational acceleration. , , z is the independent variable after the Chirp-Z transform. and Let be any positive real number. The angle of the transformed circular frequency. and This is the starting point of the polar coordinates of the independent variable z in the Chirp-Z transform. is the imaginary part, e is the natural logarithm, M is the sampling length of the vibration signal X1, and m is the signal sequence.

5. The wireless early warning monitoring method for marine oil and gas pipelines according to claim 1, characterized in that: In the sixth step, the displacement and root mean square of the offshore oil and gas pipeline are calculated respectively. The pipeline displacement is: ； in, , To obtain the vibration frequency The minimum value is the lower cutoff frequency. To obtain the vibration frequency The maximum value is the upper limit cutoff frequency. For frequency resolution, Let π be the mathematical constant, and K be the number of points in the Fourier transform. The angle is the transformed circular frequency. The root mean square of the pipe displacement is: 。 6. The wireless early warning monitoring method for marine oil and gas pipelines according to claim 1, characterized in that: In the seventh step, the vortex shedding frequency f of the offshore oil and gas pipeline... s for: ； Where Q is the measured ocean current velocity in m / s, D is the diameter of the ocean pipeline in m, and St is the Strouhal number, with a value of 0.

21.

7. The wireless early warning monitoring method for marine oil and gas pipelines according to claim 6, characterized in that: The warning threshold The value ranges from 0.8D to 1D.

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