Pipeline Location Research Articles

Parametric Study of Integral Buckle Arrestors Design of Submarine Pipeline System in Masela Block

A pipe collapse or local buckling is one of catastrophic failures that might be occurred in a submarine pipeline system due to a high external hydrostatic pressure. A preliminary survey of pipeline on the selected route shows that the pipeline will pass through a 5,309ft of depth. Buckle arrestors are necessary to be installed along a critical location of pipeline to prevent buckle propagation and catastrophic failure. The purposes of this study was to examine the effect of geometry variation, such as (i) pipe thickness, (ii) ratio of buckle arrestor thickness to pipe thickness, (iii) buckle arrestor length, and (iv) pipe diameter, of the integral buckle arrestor system to a buckling load factor. The study was conducted by numerical simulations using ANSYS™. Nominal Pipe Sizes of 28”, 30” and 32” with API 5L grade X60 materials were used in the simulation. The simulation was validated using experimental data of previous study and DNV-OS-F101. Based on this study, the buckle load factor was significantly influenced by the pipe thickness and the pipe diameter. The other two factors generate a slight change on the buckle load factor. For selected NPS of 28” with 1.2” thickness of pipeline, we hypothesize that the integral buckle arrestor with 30” length and 3.6” thickness can be used to prevent buckling propagation.

Fundamental Experiment for the Development of Water Pipeline Locator

A variety of methods for detecting the location of an underground water pipeline are being used across the world; the current main methods used in South Korea, however, have the problems of low precision and efficiency and the limitations in actual application. On this, this study developed locator capable of detecting the location of a water pipe by the use of an IMU sensor, and technology for using the extended karman filter to correct error in location detection and to plot the location on the coordinate system. This study carried out a tract test and a road test as basic experiments to measure the performance of the developed technology and equipment. As a result of the straight line, circular and ellipse track tests, the 1750 IMU sensor showed the average error of 0.08-0.11%; and thus it was found that the developed locator can detect a location precisely. As a result of the 859.6-m road test, it was found that the error was 0.31 m in case the moving rate of the sensor was 0.3-0.6 m/s; and thus it was judged that the equipment developed by this study can be applied to long-distance water pipes of over 1 km sufficiently. It is planned to evaluate its field applicability in the future through an actual pipe network pilot test, and it is expected that locator capable of detecting the location of a water pipe more precisely will be developed through research for the enhancement of accuracy in the algorithm of location detection.

Study on pipeline leaking detection and location based on intuitionistic fuzzy set theory

Study on pipeline leaking detection and location based on intuitionistic fuzzy set theory

Automatic segmentation and 3D modeling of pipelines into constituent parts from laser-scan data of the built environment

Abstract The demand for three-dimensional (3D) modeling of as-built or as-is pipelines that occupy large areas in operating plants has been growing in recent times. In practice, although measurements can be efficiently performed by the use of laser-scanning technology, generating a pipeline model from laser-scan data remains challenging, possibly due to the data characteristics. This paper proposes a method for generating 3D models of entire pipelines, including straight pipes, elbows, reducers, and tee pipes, from laser-scan data. The proposed method comprises three main tasks: (1) identifying the existence and location of entire pipelines from laser-scan data, (2) segmenting each pipeline surface into its constituent forms (straight pipe, elbow, reducer, and tee), and (3) reconstructing the geometry of the individual pipelines and generating a 3D model of it. Field experiments were performed at two different operating industrial plants to validate the method. Evaluation of the quantitative results reveals that the proposed method can indeed be used for the automation of 3D modeling of the pipelines in industrial plants—and to be capable of producing such models with high accuracy.

A Novel Method to Enhance Pipeline Trajectory Determination Using Pipeline Junctions.

Pipeline inspection gauges (pigs) have been used for many years to perform various maintenance operations in oil and gas pipelines. Different pipeline parameters can be inspected during the pig journey. Although pigs use many sensors to detect the required pipeline parameters, matching these data with the corresponding pipeline location is considered a very important parameter. High-end, tactical-grade inertial measurement units (IMUs) are used in pigging applications to locate the detected problems of pipeline using other sensors, and to reconstruct the trajectories of the pig. These IMUs are accurate; however, their high cost and large sizes limit their use in small diameter pipelines (8″ or less). This paper describes a new methodology for the use of MEMS-based IMUs using an extended Kalman filter (EKF) and the pipeline junctions to increase the position parameters’ accuracy and to reduce the total RMS errors even during the unavailability of above ground markers (AGMs). The results of this new proposed method using a micro-electro-mechanical systems (MEMS)-based IMU revealed that the position RMS errors were reduced by approximately 85% compared to the standard EKF solution. Therefore, this approach will enable the mapping of small diameter pipelines, which was not possible before.

Low-frequency Vibro-acoustic Method of Determination of the Location of the Hidden Canals and Pipelines

The problem of detecting the location of hidden pipelines laid in the ground is currently being addressed by the devices based on the method of electromagnetic location. However, this method does not provide a high accuracy and selectivity in determination of pipeline location. Furthermore, using this method it is impossible to search for non-metallic objects. The low-frequency vibroacoustic method of determination of location of the hidden channels and pipelines is suggested. The measuring and diagnostic complex with the unified application program package is developed for approbation of the suggested method.

Natural gas pipeline leak aperture identification and location based on local mean decomposition analysis

When a gas pipeline leaks, the leak aperture and its position cannot be easily identified. This paper proposed a leak aperture recognition and location method based on root mean square (RMS) entropy of local mean deposition (LMD) and Wigner–Ville time-frequency analysis. Firstly, wavelet packet energy analysis is employed to remove noise and extract the primary energy leak bands to reconstruct. The reconstructed signal is then decomposed using LMD, and the RMS entropy of PF components is calculated. The RMS entropies of multiple groups are used to build the feature vector, and it is then input into support vector machines (SVMs) to achieve the aperture recognition. An adaptive method based on mutual information is proposed to select the sensitive product function (PF) components, and the time-frequency parameters of the sensitive PF components are then calculated using Wigner–Ville distribution (WVD) method. The time delays are obtained by analyzing the time-frequency parameters. Finally the leak location was achieved by combining time delay with leak signal propagation velocity. The experimental results show that the proposed method can effectively identify different leak apertures, and the leak location accuracy is better than that of the direct cross-correlation method.

Estimation of a Pipe’s Features with In-Pipe Robot

Most of pipelines are installed under the ground, so maintaining is one of the most critical issue. Furthermore, their own locations are difficult to be identified because of its environment. For those reason, identifying the location of pipelines is widely under the research with in-pipe robots. Most methods estimate the heading direction of pipe robots as the axial direction of pipelines. However, more detail research about the axial directions of pipelines is necessary because the defined directions are not always aligned with the heading direction of pipe robot. Therefore, this paper described the estimating method of pipeline radius and its axial direction relative the robot. The relative direction and radius of a pipe are estimated from location of contact points which is determined based on geometry. Geometric equation contains highly nonlinear term, so those are obtained by the numerical form instead of closed form. The suggested method is verified by an experiment approach. Since the real relative axial direction is hard to detect, the slope of pipes are computed from estimated value and inertial measurement unit attached to the robot. Estimated radius and slope have some error in discrete curved pipe, but estimated values are well matched under straight pipes condition.

Adaptive noise cancellation based on EMD in water-supply pipeline leak detection

In water-supply pipeline leak detection and location, both the leak signals and blurred noises are closely related to the pipeline states and surroundings and most of the conventional noise-cancellation methods have to depend on the empirical parameters of either signals or noises. EMD (Empirical Mode Decomposition) is an adaptive signal decomposition method and is exclusive of base functions. A signal is decomposed into several IMFs (Intrinsic Mode Functions) in EMD, then the noise in a signal can be cancelled through removing uncorrelated IMFs. The existing EMD noise cancellation methods need to know the characteristics of either the wanted signal or the noise for rebuilding the noise-removed signal. However the characteristics of leak signals and noises are not fixed in various pipeline conditions, so the existing EMD noise cancellation methods can’t be directly applied in water-supply pipeline leak detection. This paper proposes an adaptive noise cancellation method based on EMD, in which the IMFs that don’t or less contain the components related to the leak can be removed through the cross-correlation between the IMFs and another signal collected at the either side of a suspect leak. In simulation analysis, the adaptive noise cancellation method can increase the SNRs (Signal to Noise Ratios) of leak signals as high as 16dB. In processing practical pipeline vibro-acoustic signals, with the proposed method the peak of adaptive time delay estimate of leak signals, which determines the location of a leakage, becomes more distinguished, and thus the error of leakage location is improved.

Prioritization of Reputation Loss Factor Subject to Pipeline Explosion

The impact of onshore oil and gas pipeline i.e., explosion varies depending on the pipeline location, transported product, proximity of residential areas and etc. Pipeline owner's reputation is threatened once an takes place, which influences stakeholders' perceptions consequently. This study focuses on prioritizing the importance of the reputation loss factors according to the experts' judgments. Twenty two reputation loss factors were identified from 10 major pipeline explosion post-accident case studies. Nine experts were interviewed to rate importance level of the reputation loss factors using 10-point Likert scale rating method. The significance difference was obtained by the implementation of statistical analysis. Relative Importance Index (RII) was used to identify the importance level of the factor and Analytical Hierarchy Process (AHP) method for prioritization process with the aid of Super Decisions software. Results show that all reputation loss factors are categorized within index number 4-10. The first factor with the highest importance value and priority vector corresponds to each stakeholder for both RII and AHP methods are similar, i.e., A2 Services or sales progress disturbed, B1Loss of customer confidence, D3 Severity of accident and C4 CEO refuses to take responsibility. Job application for positions is the least priority. Thus, understanding the importance of the reputation loss factors and identifying the priority of which factor to be taken care of are suggested to the pipeline operators in the post-accident responses. Hence, the reputation loss impact can be reduced and annual profit margin is secured. © 2015 Asian Network for Scientific Information.

A novel hybrid technique for leak detection and location in straight pipelines

Underground gas pipeline leaks can lead to tremendous economic loss and human injury. Therefore, it is vital to detect and locate the pipeline leaks in time to maintain the normal operation. However, continuous leak-detection methods of require a lot of manpower, marterial resources and financial supports, while other detecting activities break the normal operation of the pipeline. Hybrid techniques consisting of two or more different technologies appear to be the most probable future trend in pipeline leak detection and location field. In this paper, a novel hybrid technique based on real-time transient modeling method and negative pressure wave method is proposed. An experimental bench for straight pipelines is set up to evaluate the performance of the proposed hybrid technique, and corresponding experimental test programs for gas leak detection and location are designed and conducted. A mathematical model for the transient flow in pipelines has been established and solved under different boundary conditions. The occurrence of a leak can be preliminarily judged by the difference between the measured data and the predicted value from the model; and the changing patterns of parameters under the leak condition, the valve-opening adjusting condition and the compressor-speed regulating condition are investigated to identify the leak condition out of the operational changes. Finally, the leak point is located using the stimulus-response method. Results show that the hybrid technique is successful in detecting and locating gas pipeline leaks. It is expected that the research outcomes can serve as a technical base for the safe operation of gas supply networks.

Numerical Simulation on the Device of Rare Earth Oxide Preparation by Rare Earth Chloride Spray Pyrolysis

Based on the industrial applications of jet pyrolysis technology and it being used for the production of rare earth oxides, the paper hopes to find out an efficient, economic, and environmental friendly new technology which is suitable for production of rare earth oxides. In this paper, a chloride pyrolysis water model is designed, and standardκ-εturbulence model and VOF model were coupled to simulate the three-dimensional steady gas-liquid flow in jet reactor. The valuable parameter we got provides strong basis for the experimental equipment manufacturing in thermal state and determining test program. Conclusions show that when the drainage tube diameter is 3 mm, it can guarantee that two-phase distribution of the gas-liquid is more uniform and easy for gas-liquid mixing in the tail region of the Venturi tube. If the fluid near the middle of the duct in front of the Venturi starts to reach equilibrium as constant speed flowing, it proves that elongated pipe is conducive to obtain a stable flow of air required by experiments. In the adjustable pipeline location of the Venturi tube, fluid can form a closed loop and generate reflux in the export where atomization and gas-liquid mixing have good effects.

Estimating pipeline location using ground-penetrating radar data in the presence of model uncertainties

We study the inverse problem of estimating the pipeline location from ground-penetrating radar data in the context of Bayesian inversion. Maxwellʼs equations are used to model the electromagnetic wave propagation, and are solved using a high-order discontinuous Galerkin method. The uncertainties related to the wave propagation in inhomogeneous background are taken into account by the Bayesian approximation error (BAE) approach. The inverse problem is solved using the full waveform data. Numerical simulations suggest that by using the BAE the model uncertainties can be taken satisfactorily into account, while at the same time making a significant reduction in the computational burden. Furthermore, the estimates for the location of the pipeline are feasible in the sense that the posterior model supports the actual location.

Wireless Sensor Node for Gas Pipeline Leak Detection and Location

Many different wireless sensor nodes for gas pipeline leak detection and location has been proposed but still there are challenges particularly on environmental issues and signal accuracy. This paper discusses theories and environmental constraints for wireless sensor nodes, a case study of Dar es Salaam Tanzania and finally presents a design and simulation results of the proposed wireless sensor node using Proteus Design Suite for detecting frequency of sound exited by jetting gas, leaking from higher pressurised gas pipeline. This kind of proposed system can be useful to gas companies or industries whereby gas transportation is done. General Terms Sensor node, Gas leak detection, Pipeline monitoring, Acoustic sensor, Speed of sound in air

An Integrated Pipeline Soft-Collision Algorithm and its Implementation Based on MicroStation

The soft collision algorithm is implemented on MicroStation platform. First determine the pipeline location relationship, In view of the parallel or vertical piping and other non-parallel and non-vertical line spacing using different algorithms calculate the shortest distance. The algorithm can Meet the design requirements and reduce the amount of arithmetic operations.

Leak location of pipelines based on characteristic entropy

The leakage of oil/gas pipelines is one of the major factors to influence the safe operation of pipelines. So it is significant to detect and locate the exact pipeline leakage. A novel leak location method based on characteristic entropy is proposed to extract the input feature vectors. In this approach, the combination of wavelet packet and information entropy is called “wavelet packet characteristic entropy” (WP-CE). The combination of empirical mode decomposition and information entropy is called “empirical mode decomposition characteristic entropy” (EMD-CE). Both pressure signal and flow signal of low noise and high noise of pipeline leakage are decomposed to extract the characteristic entropy. The location of pipeline leak is determined by the combination of the characteristic entropy as the input vector and particle swarm optimization and support vector machine method (PSO-SVM). The results of proposed leak location method are compared with those of PSO-SVM based on physical parameters. Under the condition of high noise, the results of proposed leak location method are better than those of PSO-SVM based on physical parameters.

Locating Gas Pipeline Leakage Based on Stimulus-response Method

Gas pipeline leakage leads to significant environmental damages, industrial hazards and personal injuries, so detecting and locating the leakage location without delay is essential to lighten or avoid its harms. The stimulus-response method, a newly proposed technique of pipeline leakage detection and location has received much attention for its benefit of strong detecting signal and high positioning accuracy. In this paper, firstly, a complete set of gas pipeline leakage experimental device was built on the basis of stimulus-response method. Secondly, three leakage points were designed and tested to investigate the positioning accuracy. Finally, the impacts of aperture size and incentive intensity on positioning result were evaluated, and the detectable aperture size and minimum incentive intensity were determined. The results show that under fully-closed condition of the terminal valve, the minimum pore size that can be detected is 2mm in the experimental tests (with an aperture ratio of 4 percent). It is expected that the outcomes can provide reference for improving localization methods of gas pipeline leakage.

Geo-Spatial Information for the Location and Maintenance Management of Water Service Pipelines

This study examined the geo-spatial information needed for locating and maintaining water service pipelines. Geo-spatial information about the components of water service pipelines are a sine qua non for their location above, on or under the surface of the earth as well as the effective preventive maintenance of the entire water service pipelines. The Faculty of Engineering water service network in University of Benin, Benin City, was used as a case study. The geo-spatial data of the components of water service pipelines were acquired using Global Positioning System (GPS) receivers, while the attribute data were acquired using a standard checklist. Thereafter, the geo-spatial data (GPS data) were processed, and all the GPS data acquired in geographic co-ordinates were converted to plane rectangular co-ordinates, based on Minna Datum of Nigeria, using INCA GeoMATRIX software. The rectangular coordinates were exported into Autodesk Land development software, and vector model of the water service infrastructure in digital format was produced. A database was designed and created for geo-spatial and attribute information of various components of water service infrastructure (WSI). The study has revealed the locations of the burst pipes and the control valves that were malfunctioning, where the water pumped from the ground level storage reservoir, ooze out and caused artificial water scarcity in the Faculty of Engineering. The burst pipes were replaced with Unplasticised Polyvinyl Chloride (uPVC) pipes since they are nowadays most preferred for water supply piping. The control valves were also replaced with new ones. The GPS coordinates obtained in this study were used to determine the locations of the various components of water service infrastructure (WSI) in the study area. The geo-spatial and attribute information of hydraulic characteristics of the WSI has facilitated the planning, updating, operation and maintenance management of water service scheme in the study area. Furthermore, the study has provided a dynamic water service scheme of the Faculty of Engineering in digital format, which supersedes the existing, static water service scheme that is difficult to update, maintain and in analogue format. The dynamic water service scheme as well as the geo-spatial information of WSI can be updated and maintained regularly.

Stability Analysis of the Scour Protection Structure for a Debarking Pipeline

The debarking location of a gas pipeline is at the area where typhoons take place frequently and the geotechnical condition of the slope is very complex. A sloping breakwater type structure is selected in this paper for the purpose of pipeline scour protection. Since part of the sloping foundation soil consists of silty clay whose strength is very low, the bearing capacity is checked with the base pressure induced by the breakwater. The stability of the foundation of the breakwater is analyzed with the method developed by Meyerhof. The scour protection structure is proved effective and stable.

Leak location of pipelines based on transient model and PSO-SVM

An improved and integrated approach of support vector machine and particle swarm optimization theory (PSO-SVM) is first used to detect the leak location of pipelines and overcome the problem of multiple leaks. The calibration and predictive ability of improved PSO-SVM is investigated and compared with that of other common method, back-propagation neural network (BPNN). Two conditions are evaluated. One with a leak involves a set of 20 samples, while another with two leaks has 127 samples. Both internal and external validations are performed to validate the performance of the resulting models. The results show that, for the two conditions, the values calculated by improved PSO-SVM are in good agreement with those simulated by transient model, and the performances of improved PSO-SVM models are superior to those of BPNN. This paper provides a new and effective method to inspect the multiple leak locations, and also reveals that improved PSO-SVM can be used as a powerful tool for studying the leak of pipeline.