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The buried oil and gas pipeline is a linear structure with infinite length. In the shaking table test of its seismic response, it is necessary to input the spatially related multipoint seismic wave considering the propagation characteristics of ground motion. The multipoint seismic excitation shaking table tests and loading scheme of buried oil and gas pipelines are designed and formulated. The synthesis method of spatial correlation multipoint seismic wave for the buried oil and gas pipeline test is proposed in this study. The values of relevant parameters are analyzed, and corresponding program is compiled by MATLAB. The results show that the developed multipoint excitation shaking table seismic wave input scheme is reasonable. At the same time, the synthesized multipoint seismic wave based on the actual seismic record and artificial random simulation seismic wave can meet the test requirements, which suggests the testing effect is good.

Crude oil in the north-eastern state of Assam was discovered in the late nineteenth century in the eastern reaches of the state. With passage of time the oil, natural gas and petroleum products were transported from Assam to various parts of the country via pipelines. The pipelines traversing through the length of the state pass over are located close to several tectonically active faults. Some of the noteworthy faults are Oldham fault, Kopili fault and Dhubri fault. These faults have been the sources of several past damaging earthquakes (EQs) such as the 1897 Assam EQ (MW = 8.1), 1869 Cachar EQ (MW = 7.5), 1943 Assam EQ (Ms = 7.2) and 1930 Dhubri EQ (Ms = 7.1), respectively. The 1157 km long automated trunk pipeline used to carry products from Oil India Limited (OIL) and Oil and Natural Gas Corporation (ONGC) pass directly over the Kopili fault. The upcoming Barauni-Guwahati gas pipeline by GAIL will cross the Dhubri fault and will also be located very close to the Oldham fault. Thus, the pipelines are at risk of being subjected to high intensity of shaking from future earthquakes. Further, since the time of laying of the pipelines, no major or great earthquakes have occurred in Assam. Hence, the seismic vulnerability of the pipelines remains unknown. This review study is an attempt to understand the seismic vulnerability of the pipelines located in the vicinity of the Guwahati city and in case of failure its impact on the inhabitants of the city.

Актуальность исследования обусловлена необходимостью разработки эффективных технологий для обеспечения сохранности проектного положения участков магистрального трубопровода в районах c несплошным характером распространения мерзлоты. Особую актуальность работа имеет с учетом активного освоения северных и арктических нефтегазоносных районов России. Цель: разработать проектное решение и конструкцию подземных опор для закрепления нетеплоизолированных участков газопровода в сезонно-тающих и многолетнемерзлых грунтах при островном характере мерзлоты. Объекты: магистральный трубопровод, закрепленный в мерзлых грунтах. Методы: анализ и систематизация российского и зарубежного опыта теоретических и практических исследований, аналитические расчеты и компьютерное моделирование с применением программного обеспечения ANSYS на основе современных положений строительной механики и теории упругости. Результаты. Рассмотрены существующие типы опор и подвесок трубопроводов в разрезе их применимости для целей крепления подземных участков нефте- и газопроводов в многолетнемерзлых и сезонно-тающих грунтах, в том числе в местах пересечения островной мерзлоты, ледяных линз и бугров пучения. По результатам выполненного анализа возможных нагрузок и ограничений уже существующих опорных конструкций трубопроводов при рисках всплытия и провисания подземных участков в протаявшей траншее предложена конструкция подземных анкерных опор и сделаны выводы о преимуществах их применения. Для расчета нагрузок и определения требуемых размеров и количества анкеров, сечений тросов растяжек и хомута для крепления трубопровода была разработана конечно-элементная модель, эффективность которой подтверждена аналитическим путем и экспериментально на разработанном испытательном стенде. The relevance of the study is caused by the need to develop the effective technologies to ensure the preservation of the design position of the main pipeline sections in the areas with permafrost distribution. The work is of particular relevance, taking into account active development of the northern and Arctic gas and oil regions of Russia. The main aim of the research is to develop a design solution and the construction of underground supports for fixing non-heat-insulated sections of the pipeline in seasonally thawing and insular permafrost. Objects: main pipeline fixed in frozen soils. Results. The paper considers the existing types of supports and suspensions of pipelines in the context of their applicability for the fixing underground sections of oil and gas pipelines in permafrost and seasonally thawing soils, including at the intersection of insular permafrost, ice lenses and pingos. Based on the results of the analysis of the possible loads and limitations of existing supporting structures of pipelines with the risks of emersion and sagging of underground sections in the melted trench, the design of underground anchor supports is proposed and conclusions are made about the advantages of their use. To calculate the loads and determine the required dimensions and number of anchors, cross-sections of stretch ropes and a mounting clamp, a finite-element model was developed. Its effectiveness was confirmed analytically and experimentally on the developed test bench.

Globally, the integrity of girth weld (GW) of oil and gas pipelines has increased as a concern due to failures with high consequences. A primary integrity issue to pipelines considers defec...

Pipeline plays an important role in the transportation of oil and gas. In-pipe detection technology is currently widely used at home and abroad. It is of great significance to develop in-pipe detection equipment with independent intellectual property rights and suitable for the actual situation of oil and gas pipelines in China. ANSYS software is used to simulate and analyze the leakage magnetic field of pipeline defect, and the influence rule of defect size on the leakage magnetic field is explored. An in-pipe detection system based on magnetic flux leakage and eddy current detection is designed and implemented, which takes the magnetic flux leakage (MFL) detection and eddy current (EC) detection as the main detection means, mainly including detection sensor and data acquisition and storage system. The system is carried by in-pipe detection equipment to carry out a pull test in a specially-made pipe. The results show that the system has a good detection effect for various types of defects, and the results of the pull test further verify the simulation results. The in-pipe detection system combines the advantages of MFL and EC detection, and can meet the needs of the pipeline detection tasks in China.

To ensure the safe transportation of energy, Canadian pipeline operators spend roughly $1.5 billion every year on pipeline integrity. The most practiced form of pipeline integrity is the use of inline inspection (ILI) tools. To ensure that an ILI inspection occurs with minimal to no complications, operators often utilize tracking techniques for the runs. These techniques can be costly and have large safety risks and environmental impacts due to the nature of using manpower to perform the operation. Using advanced Intemet of Things (IOT) telemetry devices, the tracking of ILI tools can be completed from remote locations by installing IOT devices semi-permanently along a pipeline right -of-way. This advancement has ensured the efficient, safe and reliable tracking of ILI tools while eliminating risks involved with conventional tracking. Furthermore, the current generation of IOT telemetry devices offers a tailored suite of ILI tracking sensors such as magnetics, ultrasonic frequency, extremely low frequency (22 Hz), and geophone. This multi sensor tracking solution increases an operator’s confidence in pig passages and flow rate estimations which allows the operator to optimize pump station bypassing. Finally, the IOT telemetry devices are supported by Global System for Mobile Communications (GSM) and satellite link which has ensured global coverage to remotely track tools. The communication module for the semi-permanent tracking solution is decided based on network availability and endpoints. This paper will present a comprehensive analysis that compares conventional ILI tracking to cutting-edge IOT telemetry ILI tracking and illustrates improvements in operational efficiency, operational risk, overall safety, environmental impact, and cost-effectiveness. In addition, case studies from recent tracking runs will be shared to demonstrate advancements in IOT telemetry, tracking sensor technology, dynamic user interface capabilities, advanced data dissemination methods, and high precision benchmarking.

Oil and gas pipelines are essential infrastructures that sustain the economy of modern society. They are designed for continuous and reliable operations over their service lives. Once installed, however, their reliability is affected by several threats among which external corrosion plays a significant role. Corrosion-based pit depth growth reduces the wall thickness over time that consequently affect the mechanical strength and the hydraulic performance of the pipeline. Pipeline utility managers rely on the corrosion growth rate models to plan their maintenance, rehabilitation and/or replacement. Existing pipeline deterioration models are mostly based on the power law function that relates the pit depth with the exposure time and rarely include the soil factors that can have effect on the corrosion growth rate. Moreover, the way these factors affect the corrosion rate is complex and cannot be captured with simple linear relationship. This paper uses data found in the literature to build a nonlinear pit depth growth model based on Bayesian spectral analysis regression technique. All continuous covariates are allowed to have smooth nonlinear spectral representations of their effect function on the pit depth growth. The discrete (i.e. categorical) factors are modeled using the ordinary least squared algorithm. The final semiparametric model allows to capture all pit depth measurements, even those difficult to be modeled using high degree polynomials. The stochastic nature of the pit depth growth is captured through the Bayesian approach. A time dependent reliability analysis using subset simulation is carried out to evaluate the changes occurring in the probability of failure of the pipe over time and allow for a better planning and management of these important infrastructure. The model is applied on a bare pipe directly exposed to the soil environment over time. The Bayesian pit depth growth model is accurate enough to allow the computation of the time dependent reliability of pipelines considering both the mechanical and hydraulic reliabilities.

In the late 1960s and early 1970s, the researchers of the NG-18 committee at the Battelle Institute in Columbus, Ohio completed a seminal study on the failure pressures of flaws in oil and gas pipelines. One of the key developments was the “log-secant” equation for the assessment of axial crack-like flaws. The model was later modified to improve its accuracy and precision. The Gamma Exponent Model (GEM) was recently developed for assessment of axial crack-like flaws in pipelines. The developer recognized that the NG-18 log-secant model was theoretically derived on length, and then empirically corrected for depth. The new GEM was theoretically derived on depth, and then empirically corrected for length. The new model is similar in mathematical form to the original NG-18 log-secant model, but there are some key differences. This work is a validation study of the GEM using axial crack failure pressure data from the industry literature. Laboratory tests with machined flaws, and hydrotest and in-service failures with natural metallurgical flaws, are also considered. The results of the GEM are compared to the equivalent failure predictions using other models. The strengths and limitations of the new model are discussed in the context of improved accuracy and precision for crack assessments.

Unmanned aerial vehicles (UAVs) are now evolving as highly effective tools for tackling the requirements of oil and gas pipeline monitoring, a specific environmental application of the UAV technology. This chapter describes the current use of UAV platforms and sensors, as well as the foreseen potential of small UAV systems for monitoring oil and gas pipelines. This chapter will include sections covering the following: (i) an overview of the characteristics of UAVs; (ii) the use of UAVs for oil and gas pipeline monitoring to date with particular attention paid to the strengths and successes, as well as the weaknesses; (iii) considerations and developments in the technology of small-scale aerial platforms and sensors specifically tailored to oil and gas pipeline monitoring applications, including battery, sensor, navigation, software, and platform; and (iv) future prospects for UAV development and application.

With the accelerated construction and aging of underground oil and gas pipelines, trenchless technology (TT) has developed rapidly in recent years. This paper briefly introduces the trenchl...

Large oil and gas pipelines are prone to corrosion and leakage, so in-pipe inspection is necessary. In this article, we show a novel robot mechanism for long-distance pipeline inspection. The robot consists of three crawlers and electric putters, which can adjust their speed and radius independently. Independent adjustment and system self-checking of the robot are achieved through multiple sensors. To make the robot operate efficiently, we studied the influence of size parameters on the forces between the central body and crawler. Moreover, we investigated how to adjust the attitude of the robot through the differential speed of the three crawlers. Static and dynamic simulations of internal forces are presented. The primary experiments indicate that our robot can operate stably in a large steel pipe.

Oil and gas pipeline corrosion is highly dangerous for the environment and for the human being. In fact, this unlucky event can cause oil leakage in the environment through the rupture of the pipeline itself, while, depending on the environmental condition in which the pipeline operates, gas leakage can cause severe explosions. It is hence critical to design prediction models of the presence of corrosion in order to improve prevention and control [1]. In recent years, due to the steadily increasing availability of data, Machine Learning (ML) techniques are becoming a standard de facto in lots of different applications. Properly exploiting these techniques in the field of pipeline corrosion would pave the way to a huge improvement in the prevention and control of this dangerous problem. Unfortunately, pipeline infrastructures are not endowed with fluid-dynamical sensors, which means that an important family of descriptor for this dangerous phenomenon are not available without using simulations. This issue raises the problem of integrating and validating simulated information with real measurements of other descriptors (mainly geometrical) of the phenomenon. Therefore, in this paper, we will show how we can integrate these two different sources of data in order to build a rich and descriptive dataset representing the corrosion phenomenon in a pipeline infrastructure. We will then analyze, through a cross-correlation analysis, the relationships existing between the variables within our dataset to verify the quality of the integration procedure. Finally, we will seek for some insights in the pipeline corrosion phenomenon through a feature selection procedure, which will allow us to check whether some attributes of our dataset are privileged descriptors of the presence of corrosion in a pipeline.

Compared with the investigation of geomagnetically induced currents (GIC) in power grids, there is less study about the effect of geomagnetic disturbance (GMD) on buried oil and gas pipelines in mid-low latitude areas, which includes GIC and pipe-to-soil potentials (PSP) effects. Therefore, it is of great significance to research the GMD effect in the mid-low latitudes. For this purpose, we performed the observation experiments on GMD influencing the GIC and PSP in China’s oil and gas pipelines. The data of GIC and PSP in the pipelines are obtained, which do not pertain to the characteristics of the geomagnetic storms caused by solar activity, as well as the GIC and PSP monitoring data deriving from geomagnetic storm on May 21, 2016. By analyzing the characteristics of waveform, frequency and phase of the geoelectric fields data from Lingyang Geomagnetic Observatory ( $35^{\circ } 32^\prime \text{N}$ , $118^{\circ } 52^\prime \text{E}$ ) 60 km away in northeast from the pipeline observation site, the study corroborated that GIC and PSP variations are driven by tidal geoelectric fields (TGF) during the geomagnetic quiet days in this paper. The mechanism of GIC generated by tidal geoelectric field is analyzed. Likewise, an analysis of GMD data from the Maling Mountain Geomagnetic Observatory ( $34^{\circ } 42^\prime \text{N}$ , $118^{\circ } 27^\prime \text{E}$ ), the GIC and the PSP have been done, it is illustrated that the GIC and PSP effects are caused by TGF and geomagnetic storm induced geoelectric field together during a geomagnetic storm. The results demonstrated that, near large areas of water, the effect of tidal geoelectric field on pipeline corrosion is persistent and serious. TGF impacts the calculation accuracy of GIC in pipelines and PSP. Therefore, we should account for the errors caused by TGF when calculating GIC and PSP in pipelines near seashores and a large body of water.

Globally, more and more attention has been paid to the integrity of Girth Welds (GW) of oil and gas pipelines due to their failures with high consequences. A primary concern is that defects originate during field construction but over time may be subject to external loads due to earth movement. GW defects in newly built pipelines are also assumed to exist but would be much smaller in size, and more difficult to detect, which motivated the investigation into minimum defect detection capabilities of the inspection technologies. This study presents the evaluation results of UltraScan&trade, Circumferential Crack-Like Detection (USCCD) technology for oil pipeline GW inspection, based upon the pull test and in field data from Inline Inspection (ILI) of pipeline by PetroChina Pipeline Company (PPC) using GE PII (General Electric Company, Pipeline Integrity Inspection) 32&rdquo, UltraScan&trade, CCD Tool. The performance of USCCD is given according to the ILI data, pull test results and dig NDE (Non-Destructive Examination). It can be concluded that crack-like defects with clear edges can be detected during ultrasonic propagation, however, the irregular shape of weld makes the inspection more difficult. It is still a challenge to identify the type of defects, and depth sizing can only be classified not quantified, which would require more excavations. However, this technology is feasible for the alternative technology of GW defect inspection.

Kinetic hydrate inhibitors (KHI) and anti-agglomerants (AA) rather than thermodynamic hydrate inhibitors (THI) are often used for flow assurance in pipelines. This is because they require much lower dosages than thermodynamic inhibitors. Although the hydrate-phase equilibria are not affected, KHI and AA prevent the formed hydrate crystals from growing to a bulky state causing pipeline blockage. However, these KHIs might have huge environmental impact due to leakages from the pipelines. In this study, two biodegradable AA candidates from natural sources (that is, lecithin and lanolin) are proposed and their performances are evaluated by comparing them with and without a conventional AA (Span 80, sorbitan monooleate). At 30% and 50% water cut, the addition of AA materials was found to enhance the flow characteristics substantially in pipelines and hardly affected the maximum value of the rotational torque, respectively. Considering the cost-effective and environmental advantages of the suggested AA candidates over a conventional AA such as Span 80, the materials are thought to have potential viability for practical operation of oil and gas pipelines. However, additional investigations will be done to clarify the optimum amounts and the action mechanisms of the suggested AAs.

Over 10,000 failures have occurred in US oil and gas pipelines in the past 15 years, highlighting the significance of safety measures for such facilities. Various models have been proposed ...

In the present study, the implementation of a comprehensive mechanistic predictive model for corrosion of mild steel in the oil and gas transmission pipelines is described. The present model simultaneously accounts for all major corrosion scenarios, including CO2 corrosion, H2S corrosion, and corrosion in the presence of organic acid and also incorporates the effect of corrosion product layer formation, including iron carbonate and iron sulfide. With this approach, the present model mechanistically reflects the mainstream understanding of corrosion in such environments and can be readily used to predict the corrosion rates in industrial applications. The model was implemented by using a generalized mathematical and programming approach that has built-in flexibility to add new chemical species and additional reactions in the future. The model was designed to make it easy to extend and cover an even broader range of conditions than it currently does, such as higher temperatures and pressures, nonideal solut...

Burst capacity models and Finite Element Methods (FEM) are the most common methodologies to assess the remaining strength of corroded oil and gas pipelines. These methodologies are shown as potentially excessively conservative or to present considerable scatter in their predictions, in part because they idealize the actual shape of complex pitting by simple approximations. The new approach introduced herein employs improved Finite Element modelling of isolated complex-shaped pit geometries, uses volume loss in the burst capacity models for the first time and is validated against several existing test results. In addition, the present study assesses the accuracy of FEM–based predictions based on the simplified pit geometries and also the precision of well-known burst capacity models. A burst capacity model is proposed herein which is practical, easy to use, more accurate and more stable than all earlier well-known models.

Pipelines play a significant role in production and transportation of oil and gas. The use of film-former corrosion inhibitors is one of the most economical and reliable methods of controlling internal corrosion of oil and gas pipelines. In this paper, the general mechanisms of internal corrosion in oil and gas pipelines, formulation and chemical structure of film-forming organic corrosion inhibitors and their different types were reviewed. The mechanisms of film formation of these corrosion inhibitors are also reviewed based on electrochemical techniques. In addition, the selection process of corrosion inhibitors for pipelines is discussed.

Structural Health Monitoring techniques has captured much interest and attention of researchers owing to their potential in providing spatial and quantitative information regarding structural damage and the performance of a structure. Integrated health monitoring of structures with advances in sensor technology can improve structural reliability, system performance and safety. Pipelines exist for the transport of crude/refined petroleum, oil, natural gas and biofuels. Oil pipelines are made from steel which are usually buried. These pipelines are prone to natural and man-made damages. Hence monitoring of these buried pipelines becomes essential. Leakages of oil and gas from pipeline are dangerous for people and environment. Detection of leakage along the pipeline network is an essential part of the maintenance activity which is always a difficult task. The goal of the paper is to present the recent advancements in the field of health monitoring and assessment of in-service buried oil and gas pipelines.

Oil and gas pipelines are among the largest and most important infrastructures of the modern world. Although rare, pipeline breakdown or leakage exposes public and the environment to safety and health hazards. In this paper, a methodology to predict the external corrosion rate based on the combination of the measurement of six soil parameters and a reduced amount of inspection corrosion rate data is presented. The method provides a relatively user-friendly procedure that can be of use by the industry to focus the efforts towards optimizing the security and the continuity of the service. Furthermore, it reduces inspection costs, as a lesser number of in-situ inspections are required compared to the traditional inspection methods.

The multi-objective optimisation technique utilising genetic algorithms is employed to develop the optimal maintenance strategy for corroding oil and gas pipelines. The objective functions of the o...

Hydrocarbon fluid integrity evaluation in oil and gas pipelines is important for anticipating HSE measures. Ignoring corrosion is unavoidable and may have severe personal, economic, and environmental consequences. To anticipate corrosion's unexpected behavior, most research relies on deterministic and probabilistic models. However, machine learning-based approaches are better suited to the complex and extensive nature of degraded oil and gas pipelines. Also, using machine learning to assess integrity is a new study field. As a result, the literature lacks a comprehensive evaluation of current research issues. This study's goal is to evaluate the current state of machine learning (methods, variables, and datasets) and propose future directions for practitioners and academics. Currently, machine learning techniques are favored for predicting the integrity of damaged oil and gas pipelines. ANN, SVM, and hybrid models outperform due to the combined strength of the constituent models. Given the benefits of both, most popular machine learning researchers favor hybrid models over standalone models. We found that most current research utilizes field data, simulation data, and experimental data, with field data being the most often used. Temperature, pH, pressure, and velocity are input characteristics that have been included in most studies, demonstrating their importance in corroded oil and gas pipeline integrity assessment. This study also identified research gaps and shortcomings such as data availability, accuracy, and validation. Finally, some future suggestions and recommendations are proposed.

The article deals with the problem of connecting pipelines in the oil and gas industry. To improve the quality of welds on the oil pipeline, the article proposes an alternative method of welding and venting the beam into the atmosphere. This method includes a mobile installation for electron beam welding, in which, in manual mode, it is possible to adjust the seam speed, penetration depth, change the trajectory of the weld and the position of the installation relative to the pipe axis. Guns with a plasma cathode, which allow welding products in the atmosphere, are considered. The power of the generators is also calculated, and the generators are selected corresponding to the put forward requirements. In the course of the work, the authors are designing an electron beam welding unit, which in the future is planned to be developed as a mobile one. The mobile installation includes: a generator directing the belt to the pipe, a horizontal displacement motor, a welding positioner, an electron gun with a plasma cathode.

Landslide is one of the most harmful geological disasters for long-distance oil and gas pipelines, and evaluating pipeline vulnerability in case of landslide consequently plays an important role in improving the landslide risk assessment level. To ensure creditability, applicability and operability of pipeline vulnerability evaluation results, a physical simulation test based on the similarity principle was carried out between landslide and pipeline to verify the deformation behavior, stress and strain distribution status of pipeline in case of landslide and to acquire the empirical formula of pipeline vulnerability and distribution of thrust applied on the pipeline by landslide.

Internal corrosion due to under deposit corrosion (UDC) is responsible for at least 20% of incidents in the oil and gas industry. As a result, over the past decade, UDC has received much attention from researchers, corrosion technologists, and failure analysts. This paper briefly presents an overview of the UDC definition and types of deposits involved, as they are related to different UDC mechanisms, focusing on the commonly used methods, techniques, and sensors used to inspect and monitor the UDC in C-steel oil and gas pipelines. Additionally, the latest mitigation strategies were discussed concisely. Finally, the article highlights the limitations of the most popular testing methods and briefly discusses future challenges in this area.

Underground oil and gas pipelines are usually expected to be long-lasting. Corrosion of these steel pipelines may cause structural failures that significantly threaten life and cause environmental hazards. Therefore, developing a reliable approach to estimate soil corrosivity is important for designing a targeted anti-corrosion structure and performing risk assessment. In this study, an extension-based approach is proposed to evaluate soil corrosivity based on the following seven soil properties: redox potential, soil resistivity, pH, pipe-to-soil potential, water content, Chloride (Cl−) concentration, and salt content. Specifically, the soil was classified into five corrosivity levels, and the classic domain element, joint domain element, and element to be evaluated were established by the matter-element theory. Then, the corrosivity level was determined based on the maximum correlation degree of the multi-index to the five levels, and the final classification was obtained from the eigenvalues of the grade variables. Finally, the case study was examined to validate the application of the approach, and the results were compared to the method of buried metal specimens, which was used as a criterion. The present approach, which provided a more detailed classification, was demonstrated to be a superior choice for classifying soil corrosivity levels.