Onshore Pipelines Research Articles

Failure analysis expert system for onshore pipelines. Part-II: End-User interface and algorithm

In order to develop a Failure Analysis Expert System (FAES), with application for onshore pipeline transporting oil and gas products, the work was split in two parts. Previously failure database and knowledge acquisition method were described in the first part whereas the present, part II, the End-User interface and Algorithm are explained in detail. The proposed Failure Analysis Expert System (FAES) identifies the possible failure mechanism of onshore pipelines considering specific variables, and defining specific tests to validate the potential failure mode. The expert system training has been achieved by including variables from a structured onshore pipelines failures database. FAES showed good correlation compared to documented failure cases reported in service.

Failure analysis expert system for onshore pipelines. Part – I: Structured database and knowledge acquisition

In this article is described a knowledge-based system or expert system for failures identification in onshore pipelines. This expert system is called Failure Analysis Expert System (FAES). The FAES development has been split in two parts. In the present part I, the database structure and knowledge acquisition process are described, while in second part, the End-User interface and learning algorithm will be described. The proposed FAES includes a structured database with document processing of typical failures of pipeline collected from failure analysis reports and which were supported by expertise of failure analysis experts. A total de 854 cases of onshore pipeline failures were considered for FAES development; 683 cases for training and 171 cases for testing. Several failure mechanisms were identified with the following frequency order: external corrosion, internal corrosion, third parties, erosion, material failure, and vandalism. For machine learning, an inductive learning algorithm through Artificial Neural Network (ANN) was used.

Análise de métodos para avaliar dutos com dano mossa e sulco

A 'interferência externa', também conhecida como 'dano de terceira parte', se destaca como uma das principais causas de falhas em dutos onshore. Interferência externa pode causar, dentre outros, danos identificados como mossas, sulcos ou ambos, e também perfurações, conhecidos como 'dano mecânico'. Na literatura técnica existem alguns métodos analíticos semi-empíricos que se propoem a avaliar a adequação ao uso de dutos com dano mossa e sulco. Como as equações sugeridas por estes métodos diferem entre si, paira a dúvida sobre "qual" método daria um resultado mais exato quando aplicado. Sendo assim, este trabalho apresenta os resultados de uma análise técnica comparativa realizada para alguns destes métodos atualmente disponíveis, no tocante à fundamentação teórica, disponibilidade dos dados requeridos e exatidão em prever a tensão nominal causada pela pressão de falha. Os resultados obtidos mostram que existe uma grande similaridade entre os métodos estudados, que todos são, essencialmente, baseados na mecânica da fratura clássica, e que o 'método da fratura mossa e sulco semi-empírico original' desenvolvido pela British Gas se destaca como o 'mais recomendado' para avaliar a adequação ao uso de dutos com dano tipo 'mossa e sulco'.

Interpretation of stress-strain curve in pipeline research

For the design of on-shore pipelines installed in areas that are susceptible to ground movements and offshore pipelines, axial stresses above yield must be considered. In such so-called strain-based design,knowledge of the stress-strain behaviour of the pipeline steel and girth welds is highly important. These behaviours are influenced by many factors, including: welding parameters, operation temperature, tensile test specimen geometry and orientation, and microstructure of the steel. This paper focuses on the influence of the tensile test specimen geometry and orientation, for the case of UOE formed pipes. As regards the geometry, it is concluded that the stress-strain diagram is most representative for a flat fullthickness test specimen. As regards the orientation, the yield stress is higher for transversal test specimens, as compared to longitudinally oriented test specimens.

The Darkness Drops Again: A Recurrence of the Táin Foretold in the ‘Corrib Gas Giveaway’

This article locates an understanding of the Shell to Sea social movement (mobilised in response to the building of an onshore pipeline dispute in County Mayo) within a wider narrative which incorporates understandings of civil society containing a diverse set of ‘epic conflicts’ such as the anti-globalisation movement and neo-liberalism or phantasmagoric mythic zones and magic realism. In so doing, it puts forward a deeper understanding of the narrative of ‘the civil society’; one which has its roots in the Aristotelian civics which are integral to the ars vitae or art of living the ‘Good Life’. The article sets out a framework for understanding the Shell to Sea dispute as one where the civil society of a local rural community is targeted by the planners and shapers of a globalised type of risk-based post-modernity, causing a resistance which is embedded in the basis of civility which state, industry and society are meant to embrace and devise opportunities for, rather than having such communities targeted and undermined. The paper approaches these issues using a range of communications theories, including Habermas, narrative theory and interpretation and analysis, and identifies some of the societal strains surrounding the issue of community in (post) modern Ireland.

CO 2 maritime transportation

The objective of this study is to describe the complete transport chain of CO 2 between capture and storage including a ship transport. This last one is composed by the following steps: Shore terminal including the liquefaction, temporary storage and CO 2 loading. Ship with a capacity of 30,000 m 3. On or off shore terminal including an unloading system, temporary storage and export towards the final storage. Between all the possible thermodynamic states, the liquid one is most relevant two options are compared in the study (−50 °C, 7 bar) and (−30 °C, 15 bar). The ship has an autonomy of 6 days, is able to cover 1000 km with a cargo of 2.5 Mt/year. Several scenarios are studied varying the geographical position of the CO 2 source, the number of harbours and the way the CO 2 is finally stored. Depending on the option, the transport cost varies from 24 to 32 €/tCO 2. This study confirms the conclusion of a previous study supported by ADEME, the cost transport is not negligible regarding the capture one when ships are considered. Transport by ship becomes a more economical option compared with an off shore pipeline when the distance exceeds 350 km and with an onshore pipeline when it exceeds 1100 km.

Welding with High Power Fiber Laser API5L-X100 Pipeline Steel

The increasing length of oil and gas transportation pipelines, associated with their construction and operating costs, has lead to the development of new steel grades with higher performance. The API 5L- X100 is a new high strength steel for pipeline applications which enables the use of thinner walled pipes, lighter to transport and easier to handle on site, allowing greater operating pressures and reducing overall costs. However, this steel grade has limited ductility. Since advantages largely surpass disadvantages, these materials are being seen adequate for earthquake risk areas and low temperature environment as in the Arctic region. X100 grade is already used in northern Canada and is planed for Japan Sub Sea. Automatic metal arc welding on site is the most common method of welding onshore pipelines in steel grades X65, X70 and X80. The use of high strength steels requires the development of new welding procedures with narrow specifications and the X100 steel has limited weldability. Research is needed to develop appropriate welding procedures, avoiding typical metallurgical problems like cold cracking and toughness reduction in the weld area and to achieve high productivity and economical feasibility. This paper presents results on API X100 steel grade welded by high power fiber lasers. Since these lasers are quite new in the market, an analysis of the laser source, as well as the beam/material interaction is made. The welds produced were investigated for both macro- and microstructural analysis and mechanical properties, contributing to a better understanding of the transformations induced in this material by the thermal cycle associated with laser welding.

Extending onshore pipeline repair to offshore steel risers with carbon–fiber reinforced composites

Abstract In the last 15 years, glass fiber hoop reinforced composite systems emerged as an acceptable, successful method for repairing corroded and mechanically-damaged onshore pipelines where the primary load is internal pressure. The feasibility of extending these repairs to offshore pipes such as risers require a thorough understanding of the complex combined load profiles; overlay of significant tension, bending, internal and external pressure. Herein an innovative design based on integrated computational models and full-scale tests is presented to address the viability of reinstating capacity to offshore pipelines and risers. The experimental program was based on a collaborative test matrix developed with the participation of composite repair manufacturers. The outcome guided and led to an easily deployable carbon–fiber composite repair system which was based on limit analysis methods and strain-based design techniques. It is anticipated that the results of this program will foster future investigations by integrating operator’s insight and in situ data gathering to extend composite repair for offshore needs.

Reliability-Based Design and Assessment Standards for Onshore Natural Gas Transmission Pipelines

Onshore pipelines have traditionally been designed with a deterministic stress-based methodology. The changing operating environment has, however, imposed many challenges to the pipeline industry, including heightened public awareness of risk, more challenging natural hazards, and increased economic competitiveness. To meet the societal expectation of pipeline safety and enhance the competitiveness of the pipeline industry, significant efforts have been spent for the development of reliability-based design and assessment (RBDA) methodology. This paper will briefly review the technology development in the RBDA area and the focus will be on the progresses in the past years in standard development within the American Society of Mechanical Engineers (ASME) and the Canadian Standard Association (CSA) organizations.

Esso Australia's process safety management process

Safety is a core value at Esso Australia. We strive to observe the highest standards of safety to ensure that nobody gets hurt in our operations. We believe this goal can be achieved through a broadly shared commitment to personal and process safety—both of which are managed using our operations integrity management system (OIMS). In the Gippsland region of Victoria, Esso Australia operates oil and gas production facilities ranging from sub-sea completions to substantial staffed offshore facilities, an onshore crude stabilisation, three gas processing plants and a natural gas liquids fractionation plant, all interconnected by a network of offshore and onshore pipelines. Every day Esso’s Gippsland operations produce millions of litres of crude oil and millions of cubic meters of natural gas. Having all this fuel energy flowing through these plants each day at high pressures, and widely ranging temperatures, it is imperative that it is safely controlled and contained by the process equipment. How do we do this? With process safety systems. Process safety is a crucial component of OIMS that ensures Esso’s assets are operated and maintained in keeping with corporate and industry safety standards. In this presentation we show how process safety is managed within OIMS and how the people within Esso individually and collectively contribute to it. Our work in this area has recently been captured in a training package that includes a DVD shown at the conference. It was created to raise the awareness and understanding of all Esso employees about the principles that underpin Esso’s approach to process safety. This abstract outlines how we approach process safety across the life-cycle of our facilities and the role people play in managing this very important aspect of our work. Our training reinforces the message that responsibility for effective management of process safety lies with every employee and how OIMS is designed to assist people to achieve the desired results where all risks are appropriately managed. We have sought to connect the concepts used to manage personal safety, which are well understood by the workforce, with those that are needed to understand how to manage process safety.

Characterization and Evaluation of the Integrity of the Onshore Pipelines

ABSTRACTThe pipelines are the main transport and distribution system of production in the oil industry, which are subject to environmental and operational conditions which are not favorable for the operation of the pipelines and sometimes represent the risk of accidents and high economic losses. The evolution of risk begins with a systematic search of possible threats to the integrity of the pipeline. The identification of potential threats should not be limited to known risk categories reviewed, but must complete the steps to find new and unique expressions of risk and the study of particular cases. Thus, the importance of a comprehensive risk assessment of the transmission pipeline is crucial. In this paper an integrity assessment for corrosion damages in pipelines was developed through a methodology based on risk analysis to estimate the propagation rate on the time, the size, location and number of damages. To perform this study a data obtained from smart pig runs and an artificial neural network (ANN) model with retro propagation was used. From the data obtained from launching smart pigs on the pipeline it was carried out the training of the neural network, later on it was applied the network previously trained to get the predictions of damages on the pipeline, considering that pipeline did not have any maintenance.

The Use of QRA To Inform the Design of a High-Pressure Onshore Pipeline

Summary The management of onshore-pipeline safety in the United Kingdom is governed by the Pipelines Safety Regulations, 1996. This requires pipeline operators to design, build, and operate pipelines to ensure that they are safe, so far as is reasonably practicable. This is achieved, in part, by applying good practice and designing the pipeline to recognized onshore-pipeline design codes. Where the proposed design falls outside code guidance, a quantitative risk assessment (QRA) provides an effective means of demonstrating a safe design. This paper describes a study that was carried out to define the design requirements for the onshore section of a multiphase pipeline. The proposed pipeline will have a design pressure of 380 barg. However, onshore design codes PD 8010-1 (2004) and IGE/TD/1 (Steel Pipelines 2001) do not provide guidance on the design of pipelines with pressures exceeding 100 barg. Experience from other projects indicates that it is important to consider the implications of such high design pressures early in a project. The QRA considered a number of different design options. The safety risks of the proposed pipeline options were compared with those from a typical 100-barg-gas-transmission pipeline of the same diameter. This means that the risk of the proposed pipeline can be compared in a relative manner, to an acceptable design, and in an absolute manner to limits on individual and societal risk. The results of QRAs of the different design options are summarized and discussed. The effects of mitigation measures, such as reducing the pipeline-design factor (the ratio of the hoop stress to the specified minimum yield strength), increasing the wall thickness, and incorporating a pressure-limiting system at the landfall, are illustrated. It is shown that the proposed design is feasible. The individual and societal risks for the proposed design were lower than that of a typical 100-barg-gas-transmission pipeline. The individual risk was in the broadly accepted region of risk, as defined by the UK Health and Safety Executive (HSE), and the societal risk was below the acceptance criterion given in IGE/TD/1 (Steel Pipelines 2001).

Safety and Loss Management System for Pipelines

Management systems have had long widespread acceptance in many industries for various applications: notably, quality, safety, and environment. In recent years, the North American onshore pipeline industry has started adopting management system principles for the management of pipeline integrity. This paper discusses the rationale for adopting a systems approach to safety and presents a safety and loss management system template that may be used for the full life cycle of a pipeline, from concept to abandonment.

Reducing Pipeline Construction Costs: New Technologies

The Oil and Gas industry is constantly looking for ways to reduce capital investment for new projects while maintaining performance and quality standards. As the demand for oil and natural gas increases, so does the need for an expanded network of onshore and offshore transmission pipelines. However, the capital investment associated with new pipelines is enormous. There are a number of materials joining technologies that are being investigated to reduce pipeline construction costs. This document presents three technologies showing particular promise: laser pipeline welding, the use of high strength pipeline materials, and advanced automatic inspection. Test have shown that the HLAW process, which combines the LBW and GMAW processes, is felt to offer a number of benefits in terms of higher potential productivity, ability to produce welds with excellent material properties and a reasonable tolerance for fit-up variations. For existing laser power levels, a viable scenario for implementation of lasers for pipeline welding applications is the use of HLAW for root bead welding, followed by joint filling with conventional mechanised GMAW-P. Concerning the use of high strength pipeline materials, results of a project are presented. The primary objective of this study was to evaluate the mechanical properties of weld metals deposited using a number of commercially available welding consumables and welding processes. This work included characterization of weld metal microstructure, HAC susceptibility of the GMA weld metal and X100 base metal, and solidification cracking of selected welding consumables. The project evaluated commercially available consumables using several welding processes and shielding gases. The third part of the document covers results of a project aiming to collect third-party independent data and statistically characterise the systematic and random errors in girth weld defect sizing, as measured by mechanised ultrasonic testing P/E, TOFD methods and PA ultrasonic technology, in support of pipeline reliability assessments. The defect sizing accuracy of the automated ultrasonic testing (AUT) of girth welds was evaluated using zonal discrimination with focused and non-focused search units arranged for P/E and TOFD methods and PA technology. The objectives were achieved by conducting “open” and “blind” UT trials. NDE flaw verification and destructive testing for flaw size validation were performed. AUT data were collected and statistically analysed.

THE MINERVA GAS FIELD EIA—A CASE STUDY OF COMMUNITY INVOLVEMENT IN DECISIONMAKING

The Minerva gas field is situated approximately 10 km offshore Port Campbell, Victoria, in the Southern Ocean in water depth of approximately 60 m. The development involves the drilling and completion of two wells, offshore pipelines to the coast, subterranean shore crossing and onshore pipelines to a gas treatment plant where liquids will be removed prior to exporting the gas.From the outset, the project attracted the interest of the local and wider community due to its proximity to the highly regarded Port Campbell National Park. The National Park is known for its unique geomorphological features, its fauna and flora and aboriginal heritage sites.The development has been subject to a dual jurisdiction, State and Federal, Environmental Impact Assessment (EIA) process. The process included the formation of a Community Consultative Committee consisting of representatives from government agencies, local community groups, environmental groups, industry associations and the proponent. The Committee provided input to the scope of the EIA and reviewed and endorsed the studies and report prior to public exhibition. An independent panel hearing and ministerial assessments followed public exhibition.A phased process was adopted in the selection of routes, sites and technologies to achieve the lowest practicable environmental impact. Each phase was supported by studies of environmental aspects, fauna, flora, heritage, visual and social impacts. The process commenced on a regional scale and progressively refined the concept and the study area. Detailed studies of key environmental aspects were conducted for the selected development options.The final development concept addressed the key findings of the baseline and subsequent environmental studies and was largely supported by an independent panel. However, there still remained concerns by sectors of the community on the issue of precedent and integrity of the National Park. The Ministerial assessment reflected the issues of community value above technical, environmental, archaeological and heritage considerations.

The Pipeline Industry-Planning and Exercising: Is Industry Deriving Full Benefit from Lessons Learned?1

ABSTRACT The National Preparedness for Response Exercise Program (PREP) was developed to provide a mechanism for compliance with the exercise requirements established under the Oil Pollution Act of 1990 (OPA 90), while being economically feasible for the government and the oil industry to adopt and sustain. PREP provides the opportunity for both the government and oil industry to participate in a standardized exercise program to meet all OPA 90 mandated exercise requirements. The guidelines also state that plan holders are responsible for addressing issues that arise from the evaluation of exercises, and for making changes to the response plans necessary to ensure the highest level of preparedness. This paper outlines the planning and exercise program established by the Department of Transportation's Office of Pipeline Safety for onshore transportation-related pipelines. It presents a compilation of lessons learned from over 45 unannounced exercises conducted since 1996, which identified improvements in the area of emergency management. The report also chronicles the oil pipeline industry's revisions to response plans based on recommendations from the PREP exercises. Finally, the report offers recommendations to ensure that the pipeline industry incorporates the lessons learned from PREP into its response plans and corporate response structure.

Estimating the Cumulative Cost of OPA 90 to Private Industry

ABSTRACT The purpose of this paper is to estimate the cumulative cost incurred by private industry as a result of the various regulations enacted under the Oil Pollution Act of 1990 (OPA 90) and to compare these costs against the estimated effectiveness of the program in terms of avoided future oil spills. The authors reviewed Federal Register announcements of federal agency rulemakings to identify estimated costs to industry and to determine if reported costs are one-time occurrences for capital-related expenditures or represent annual estimates for repeated activities. The authors then estimated the total costs of each rulemaking through the year 2015. The costs of regulations implemented under OPA 90 that impact the private sector range from zero to $3.5 billion in discounted dollars. Based on these individual government estimates for each OPA 90 regulation, the authors estimate the discounted cost to industry to comply with all of the OPA 90 requirements to be $12.1 billion, the largest portion of which affects the marine vessel industry. Total benefits of the rulemakings are estimated to exceed 3.6 million barrels of avoided oil spills through the year 2015. Over one-half of this benefit estimate results from the facility response planning requirements for non-transportation-related on-shore facilities and pipelines. The cost effectiveness of regulations implemented under OPA 90 ranges between several hundred dollars to over $26,000 per barrel of avoided oil spill.

Seismic Assessment for Offshore Pipelines

An international consensus on seismic design criteria for onshore pipelines has been established during the last 30 years. The need to assess seismic design for offshore pipelines has not been similarly recognized. The geotechnical hazard for a pipeline routed across steep slopes and irregular terrains affected by earthquakes are discussed in this paper. The integrity of both natural and artificial load-bearing supports are assessed. The response of the pipeline to direct excitation from soil or through discontinuous, sparsely distributed natural or artificial supports are commented on. Some applications are given in order to point out topical aspects and major design issues for currently operating offshore pipelines crossing seismic active seabeds.

Erste Erfahrungen bei der Detektion von Rissen in Fernrohrleitungen mit Impuls‐Wirbelstrom

AbstractErdverlegte Fernrohrleitungen werden mit sogenannten Molchen auf deren Zuverlässigkeit untersucht. Für die Prüfung auf Innenrisse wurde ein Molch auf Impulswirbelstrombasis entwickelt. Der Aufbau des Molches, das verwendete Wirbelstromverfahren und erste Meßergebnisse werden beschrieben. Die Vor‐ und Nachteile werden aufgezeigt.

Computer Control — Key to Effective Pipeline Operation

Process information is transferred through a geostationary satellite, troposcatter links, radio systems, cable following the onshore pipeline route and leased telephone lines. The information made available to the gas controllers through the data acquisition and simulation data programs is applied to solve problems and make decisions that affect all phases of the delivery of gas energy.