bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Collaborative Approach to Safety: Applying Lessons Learned From Other High Risk Industries
Authors: Munro John , Sommer Garry 
Published: January 2019

Pipeline companies are facing an unprecedented era of challenges at an industry-wide scale. Recent incidents have increased public attention and criticism, cast doubts over the industry’s safety performance, and resulted in growing regulatory pressures. However, such a story is not unique to the pipeline sector. Other high-risk industries have experienced similar trials, and history may provide a blueprint for pipeline operators to follow.
This paper examines industries which have undergone significant changes in behavior due to catastrophic incidents. To address safety performance issues, public outcry and regulatory concerns, these industries emphasized the need for greater collaboration. Whether through encouragement of best practices via self-governance models, increased learning from incidents through sharing of data, or providing support to companies that were lagging behind, they concluded that it was imperative to move forward in a coordinated, collaborative fashion. Companies could no longer be satisfied with exceptional performance within their own walls, as they were ultimately answerable to the performance of their industry as a whole.
In many ways the pipeline industry has similar challenges to face. The relatively low frequency of high consequence incidents means that it is difficult for any single operator to gather statistically meaningful trends. ILI technology requires vast quantities of data to understand, validate and improve performance; quantities beyond what any single operator is likely to possess. No operator can effectively address the challenges of today’s environment single-handedly. It is only through coordinated, collaborative engagement throughout industry that rapid and meaningful improvement to pipeline safety will be achieved.
This paper suggests a variety of possible strategies and is intended to encourage discussion among leadership and managers regarding how the pipeline industry can come together more effectively to address industry safety issues in a unified fashion.
The Effect of Corrosion Growth Model Assumptions on the Reliability Estimates of Corroded Pipelines
Authors: Dann Markus R. , Huyse Luc 
Published: January 2019

Corrosion growth models are used to estimate future metal loss and the safe remaining lifetime of corrosion features in pipelines. Probabilistic models have become increasingly important in practice for reliability and risk-based pipeline assessments. The unknown model variables are usually determined from in-line inspection (ILI) results. Corrosion growth models exhibit various levels of complexity to account for temporal and spatial uncertainties of the actual corrosion growth process, and measurement uncertainties associated with ILIs. Model diversity leads to significant differences in how the models approach the uncertainty of future corrosion growth.
This paper builds upon previous work and provides some theoretical background to an application described in [1]. It compares four common probabilistic corrosion growth models with respect to reliability estimates of leak failure. The four models are two uncertain corrosion rate models and two stochastic process models where the features are considered to be either independent or exchangeable. The unknown random variables of each model are updated in a Bayesian manner using the same ILI results. The key findings of this paper are:
• Proper truncation at zero of the probability distributions for the unknown random variables is necessary if the measured corrosion growth is near zero or negative.
• A stochastic process leads to lower uncertainties when determining future metal loss and, consequently, an increased reliability against leak failure than corrosion rate models.
• The assumption of exchangeable features causes a reduction in the probability of leak failure due to the effect of borrowing information compared to independent features.
The four corrosion growth models provide similar results with respect to the probability of failure if the measured corrosion growth is large. As the measured corrosion growth decreases in size, the differences between the reliability estimates increase.
Design of Experiment and Validation of Model for Offshore Buried Pipeline Thermal Analysis
Authors: Chakraborty Suvra , Talimi Vandad , Muzychka Yuri , McAffee Rodney , Piercey Gerry 
Published: January 2019

Buried pipeline heat transfer modeling has become an important topic in the Oil and Gas industry. The viscosity of fluid i.e. crude oil travelling through the buried pipeline largely depends on the flow temperature and pressure. The aim of this paper is to give an overview of designing the experiment for heat loss from offshore buried pipelines and validation of the experimental model using analytical solution and CFD modeling.
Several benchmark tests have been performed to ensure the validity of the test using theoretical shape factor models which depend on the amount of heat flow, thermal conductivity and geometry of the surrounding medium. This theoretical model has limitations such as the assumption of uniform soil properties around the buried pipeline, isothermal outer surface of the buried pipeline and soil surface. This paper illustrates several steady state and transient experiments to simulate the mechanism of heat loss from an offshore buried pipeline along with the experimental procedures. This paper also shows the transient response for shutdown tests performed in dry sand medium with numerical runs as well. With the progress of the research, several investigations will be made using different burial depths and diameters of the buried pipeline with backfill materials and trenching for different soil conditions, affecting the actual behavior of the model.
Multi-Phase CFD Modelling of CO2 Releases From High-Pressure Pipelines
Authors: Liu Xiong , Godbole Ajit , Lu Cheng , Liu Bin , Venton Philip 
Published: January 2019

An accurate prediction of the ‘source strength’ of CO2 released from high-pressure pipelines is of great importance for risk assessment, because this parameter determines the subsequent dispersion in the atmosphere. The widely used method is to employ a one-dimensional discharge model describing the conservation of mass, momentum and energy. The fluid is usually considered to remain at thermal and mechanical equilibrium during the depressurisation process, while the non-equilibrium liquid/vapour transition phenomena are ignored. Although efforts have been made to model non-equilibrium, two-phase CO2 depressurisation in recent years, possible improvement can be made by using a more precise Equation of State (EOS) and more detailed models.
In this paper, a multi-phase Computational Fluid Dynamics (CFD) model is presented to simulate CO2 releases from high-pressure pipelines. A real gas EOS (GERG-2008) was incorporated into the CFD code. This enabled accurate modelling of the thermodynamic properties to achieve a more precise source strength estimate. The non-equilibrium liquid/vapour transition was modelled by introducing source terms for mass and latent heat. A ‘time relaxation factor’ was used to control the inter-phase mass transfer rate. The CFD model was validated against experimental results from the British Petroleum (BP) CO2 release trials. The optimum relaxation time (for the CO2 depressurisation cases tested) was obtained through simulations by varying the time relaxation factors and comparison with experimental data. In addition, the effect of the relaxation time on the source strength prediction is discussed.
A Case Study on the Application of Structural Reliability Analysis to Assess Integrity for Internal Corrosion of Unpiggable Pipelines
Authors: Taylor Katherine , Turner Susannah , Goodfellow Graham 
Published: January 2019

Operators wish to understand the condition of their pipelines to manage ongoing integrity. Information on the condition of the pipeline along its entire length can be obtained using in-line inspection (ILI). However, some pipelines cannot be internally inspected due, for example, to tee connections, tight bends, low flow or to a lack of launcher and receiver facilities. The condition of these ‘unpiggable’ lines can sometimes be largely unknown. To aid the understating of the pipeline condition without ILI data, operators will often rely on alternative sources of information, such as localised external inspections, model predictions and company and individual experience. However, there may be significant uncertainty associated with these alternative data sources when using them to assess the condition of the entire pipeline. This uncertainty may be understood by applying a probabilistic approach to the assessment of pipeline integrity using structural reliability analysis (SRA) methods.
An SRA approach applies probabilistic input parameters to a failure prediction model for a defined limit state function. Previous IPC papers[1,2,3] have presented guidance on probabilistic assessments to model pipeline failure. Recommended probability distributions are presented which account for uncertainties associated with line pipe properties, defect sizing and the error associated with the predicted failure model. However, there is little published guidance readily available on recommended defect characteristic distributions specific to internal corrosion features. Parameter distributions are recommended for defect sizing based on empirical data, which are mainly used for external corrosion features.
In this paper, a case study is used to present a practical application of an SRA methodology for assessment of pipeline integrity with respect to internal corrosion. Discussion is presented on alternative sources of information for the assessment when ILI data is unavailable, including targeted external inspections of unpiggable lines and data sets from comparable piggable lines. Probability distributions are derived from the available inspection data for the internal corrosion feature size and corrosion rate input parameters to the SRA. Probabilistic analysis is used to account for the expected population of unknown features in the uninspected parts of the pipelines. The expected feature size, corrosion rate and feature density calculated are used in the SRA to estimate the total probability of failure due to internal corrosion over time for the entire length of the pipeline. Recommendations are provided on the application of an SRA methodology to assess pipeline failure due to internal corrosion.
Strain Capacity and Deformation Behavior of HFW Linepipe
Authors: Igi Satoshi , Yabumoto Satoru , Sadasue Teruki , Tajika Hisakazu , Oi Kenji 
Published: January 2019

Newly-developed high quality high frequency electric resistance welded (HFW) linepipes have recently been applied to offshore pipelines by using the reel-lay method and onshore in extremely low temperature environments because of their excellent low temperature weld toughness and cost effectiveness. In order to clarify the applicability of these HFW linepipes to seismic regions, a series of full-scale tests such as the bending test with internal pressure and the uniaxial compression test were conducted according to the seismic design code of the Japan Gas Association (JGA).
Based on these full-scale tests, the safety performance of high quality HFW linepipe when applied to seismic regions is discussed in comparison with the mechanical properties obtained in small-scale tests, such as the tensile and compression properties of the base material and weld seam, focusing especially on the compressive and tensile strain capacity of HFW linepipes from the viewpoints of full-scale performance and geometrical imperfections.
The results of the bending test under internal pressure and the uniaxial compression test without internal pressure complied with the JGA seismic design code for permanent ground deformation induced by lateral spreading and surface faults.
In addition, a full-pipe tension test was also conducted in order to investigate the tensile strain capacity of HFW linepipes for axial deformation.
Critical Review of Risk Criteria for Natural Gas Pipelines
Authors: Tomic Aleksandar , Kariyawasam Shahani 
Published: January 2019

Risk Assessment is an integral part of an Integrity Management Program (IMP), and it is generally the first step in most IMPs. Risk is of the product of two variables, the likelihood of failure and the consequence of failure, where failure is defined as a loss of containment event. Hence, it is necessary to calculate both variables in order to accurately model risk. To assess risk, criterion need to be established and the actual risk needs to be compared to the criterion in order to determine the acceptability of risk.
Currently, most industry risk assessment models are qualitative risk models, where consequence is generally characterized by class, relative population measures, or some other relative measure. While this may be adequate for some relative risk ranking purposes, it is generally not accurate in representing the true consequences and the arbitrary nature leads to overly conservative or overly un-conservative results.
Conversely, Quantitative Risk Assessment (QRA) models take into account the effect of the thermal radiation due to ignited pipeline rupture and evaluate the consequence on the surrounding human population. Such a consequence model is dependent on the pipeline properties (i.e. diameter and MOP) and the structure properties (i.e. precise locations and types of structures). The overall risk is then represented by two specific, well defined measures: Individual Risk (IR) and Societal Risk (SR). The goal of this paper is to perform a critical review of IR and SR acceptability criteria that are widely available and widely used, and outline the criteria (and the approach) adapted by TransCanada Pipelines.
Worldwide, there are several different standards that define the criteria for evaluating IR and SR, particularly some countries with higher population densities around pipelines (e.g. UK and Netherlands). These IR and SR criteria have been compared in a hypothetical case study, to determine the most appropriate method in terms of the assumptions for calculating risks, the criteria, and how the actual risks compares to the criteria. The outcome of this study was the adoption of a defendable process for calculating SR, along with the associated criterion.
Failure Frequency Calculation of Transmission Pipelines or Stations due to Nearby Wind Turbines
Authors: Coster Roelof P. , Middel Martijn T. , Dröge Marc T. 
Published: January 2019

The present article discusses the methodology to include potential wind turbine failures in quantified risk assessments (QRA) of transmission pipelines or stations, which is included in the latest version of the Dutch national ‘Handbook on Risk Zoning of Wind Turbines’ (‘Handboek Risicozonering Windturbines’) [1].
The methodology includes a simple set of wind turbine failure modes and frequencies, probability density functions and failure criteria of the impacted underground pipeline or aboveground station components. Using the methodology, an additional failure frequency can be calculated for a transmission pipeline or a station due to the presence of one or several wind turbines.
The focus of the methodology is not on the physics of each of the separate scenarios (many different studies and approaches are publically available), but as a practical tool for quantified risk assessments and determination of acceptable siting distances for wind turbines near gas infrastructure. The pressure and the (possibly non-uniform) construction parameters and depth of cover of underground pipelines are taken into account in the calculations.
The methodology shown in this article was developed by DNV GL and published in Netherlands Enterprise Agency’s ‘Handbook on Risk Zoning of Wind Turbines’ in May of 2013. Following the publication of this Handbook, a software tool has been developed to implement the calculation method. This software is also discussed in this article.
Advanced Pipeline Welding Technologies for Strain-Based Design
Authors: Wasson Andrew J. , Fairchild Doug P. , Noecker Fredrick F. , Macia Mario L. , Nissley Nathan E. 
Published: January 2019

In order to meet the increasing worldwide energy demand, there is a need to economically develop remote oil and gas resources. Construction of pipelines is required to connect these resource locations to markets. Such pipeline routes may cross areas of large ground motions such as regions of active seismicity, discontinuous permafrost, and offshore ice gouging. All of these features can subject pipelines to significant longitudinal strains. For these conditions a strain-based design (SBD) approach may be required to maintain pipeline integrity.
Welding technology is a key component of pipeline construction. Significant pipeline construction cost savings are enabled with the use of higher strength steels (X80+). Higher strengths enable reduced pipe wall thicknesses, which reduces both weight and girth welding time. However, robust welding technology for high strength SBD pipelines remains challenging. Such applications demand welds with both high strength (&gt;120ksi) and low temperature (−15°C) toughness, combinations that are at the limits of, or beyond, existing commercial technology. This paper discusses the development of an enabling welding technology which offers a superior combination of strength and toughness properties.
An iron-nickel (FeNi) martensitic weld metal with a refined mixed cellular microstructure has been developed as a promising high strength weld metal that can be applied for field pipeline construction. This paper describes how this technology has been applied to create welds for X80 strain-based pipelines requiring significant weld strength overmatch and superior ductile tearing resistance. The welding technology can also be applied to X70 grade strain-based pipelines where high toughness is required. This approach has been developed for mainline girth, tie-in girth, and girth repair welding scenarios. Welding procedures are discussed and examples of the mechanical properties achieved and calculated strain capacities are described.
Adapting Safety Culture Assessments to the Pipeline Industry
Authors: Maddin Kimberly , Shanks David A. 
Published: January 2019

Safety culture is a concept which has garnered increasing interest within the pipeline industry in recent years. Made up of the attributes and values of a company as well as the perceptions and values of the individuals within it, safety culture reflects the organization’s commitment to safety. Improvement of an organization’s safety culture can result in a reduction in the frequency of undesired events.
The assessment of safety culture presents a number of challenges, including the appropriate selection of models and data gathering methodologies that provide measurable and repeatable results and address both personal and process safety; the development of action plans which drive change within the appropriate levels of an organization; and the measurement of improvement efforts and outcomes.
The objective of this paper is to share lessons learned and guidance based on experience conducting semi-quantitative safety culture assessments. This paper will describe: researching and selecting a safety culture assessment model; selecting, developing, and customizing the assessment methods (e.g. document review, surveys, interviews, and observations); undertaking the assessment itself; quantifying and analyzing the findings of the assessment; developing recommendations that improve safety culture; and considerations for the implementation of action plans to ensure continual improvement.
The guidance provided in this paper is intended to help organizations improve the safety culture at all levels of the business in order to advance both personal and process safety performance.
Effect of Block Valve and Crack Arrestor Spacing on Thermal Radiation Hazards Associated With Ignited Rupture Incidents for Natural Gas Pipelines
Authors: Rothwell Brian , Dessein Thomas , Collard Andy 
Published: January 2019

A study was undertaken to evaluate crack arrestor and mainline block valve (MLBV) spacing distances beyond the limits defined in the 49 CFR Part 192 for Class 1 locations for the design of a 42-inch (1,067-mm) OD arctic pipeline. The study assessed whether an MLBV spacing longer than that required by 49 CFR Part 192 for Class 1 locations can provide a level of safety equivalent to that afforded by the spacing recommended in the code. This was accomplished by comparing the hazards in terms of the volume of natural gas released over time, the potential for damage to surrounding structures, and the life safety risk to personnel and the public. The analysis was performed using the software tool PIPESAFE (version 2.20.0), which was developed for a group of pipeline operators by Advantica Technology (now DNV-GL).
A full transient analysis of the flow inside the pipeline and through the rupture opening was carried out with automatic shut-off valve (ASV) closures simulated as boundary condition changes at the locations of the valves triggered by the local transient pressure. Gas outflow rates were fed to a structured flame model that calculates the temperature distribution within the flame and the radiant energy emitted and uses the latter to determine the incident thermal radiation field in the area surrounding the rupture, the associated hazard areas and the accumulated thermal radiation dosage over time. These results were compiled into contour plots of thermal radiation intensity for different times; plots of the total area within specific contours of thermal radiation intensity for different times; and plots of the total area within specific contours of accumulated dosage. The dosage-area curves facilitate a direct comparison of the various MLBV and crack arrestor spacing options considered within this study by providing a simple means to establish if the change in spacing causes a substantial change to the affected areas for dosages up to the limits associated with specific levels of lethality to humans and for piloted ignition of wooden structures.
It was found that valve spacing has a strong effect on the time at which closure begins to affect the outflow rate. The decline in flow rate after valve closure had significant influence on the thermal radiation field, but these effects only occurred at a relatively late stage. Increasing fracture length led to considerable changes in the shape of the thermal radiation field, but the total footprint within which casualties might be expected in the event of an ignited rupture release and the severity of injuries within the footprint are unaffected by valve closure under the assumed conditions. Similarly, the damage potential to surrounding buildings was unaffected by valve spacing, indicating that increased valve spacing could be implemented in remote, low population density areas without affecting safety.