scholarly journals A Methodology to Maintain Pipeline Integrity at Water Crossings

2000 ◽  
Author(s):  
Z. Joe Zhou ◽  
Gary Beckstead ◽  
Jason Westmacott ◽  
Alan Samchek ◽  
Moness Rizkalla
Keyword(s):  
Failure Probability ◽  
Pipeline System ◽  
Stream Power ◽  
Fiscal Responsibility ◽  
Weather Patterns ◽  
System A ◽  
Lateral Erosion ◽  
Scour Hazard ◽  
Local Water ◽  
Remedial Work

As the pipeline system of TransCanada Pipelines Ltd. (TransCanada) ages, cover at water crossings is continuously being adjusted to dynamic changes in weather patterns and local water crossing hydraulic characteristics. In an increased asset base of over 37 000 km of pipeline, this creates challenges to find and remediate crossings with high risks while maintaining the integrity of the whole system. A methodology has been developed to address the increasing demands of fiscal responsibility and pipeline integrity. The Scour Hazard Database Model (SHDM) provides the necessary tool to provide solutions to both of these challenges. The SHDM provides a stand alone prioritisation tool that is updateable and transparent. It can alert TransCanada to both immediate and potential pipeline exposures, in order that reactive and proactive solutions can be initiated. The SHDM contains descriptive pipeline information, local hydrologic data, channel hydraulic information, and scour hazard logic for over 2350 river and creek crossings throughout Canada. This information is used to produce a final rating value for comparing the potential for vertical and lateral pipeline exposures at each crossing. The vertical scour logic considers age of the crossing, modelled scour, natural degradation and any remedial work to determine the rating value. The lateral erosion logic uses channel form, location, lateral cover distances between the thalweg and pipeline, stream power, age of the crossing, and any remedial work to develop the lateral scour rating value. Furthermore, the exposed pipes are evaluated based on the potential failure mechanisms to determine failure probability. Included in the failure analysis are lateral stability, impact of debris, and fatigue. The failure probability and the consequence of the failure are used to rank the crossings and identify the requirement for maintenance activities.

Optimization of Operation Parameters for Direct Spring Loaded Pressure Relief Valve in a Pipeline System

2018 ◽  
Vol 140 (5) ◽  
Author(s):  
Hyunjun Kim ◽  
Sanghyun Kim ◽  
Youngman Kim ◽  
Jonghwan Kim
Keyword(s):  
Pressure Relief Valve ◽  
Pipeline System ◽  
Relief Valve ◽  
Pressure Relief ◽  
Computational Costs ◽  
Constant Degree ◽  
System A ◽  
Disk Mass ◽  
Analysis Scheme ◽  
Surge Control

A direct spring loaded pressure relief valve (DSLPRV) is an efficient hydraulic structure used to control a potential water hammer in pipeline systems. The optimization of a DSLPRV was explored to consider the instability issue of a valve disk and the surge control for a pipeline system. A surge analysis scheme, named the method of characteristics, was implemented into a multiple-objective genetic algorithm to determine the adjustable factors in the operation of the DSLPRV. The forward transient analysis and multi-objective optimization of adjustable factors, such as the spring constant, degree of precompression, and disk mass, showed substantial relaxation in the surge pressure and oscillation of valve disk in a hypothetical pipeline system. The results of the regression analysis of surge were compared with the optimization results to demonstrate the potential of the developed method to substantially reduce computational costs.

Mantle flow and orography: the effect of basal lithospheric shearing and lateral erosion gradients on continental rifting

2021 ◽  
Author(s):  
Pietro Sternai
Keyword(s):  
Mantle Plume ◽  
Sedimentary Basins ◽  
Windward Side ◽  
Ethiopian Rift ◽  
Mantle Flow ◽  
Stream Power ◽  
Main Ethiopian Rift ◽  
Extensional Tectonic ◽  
Continental Rifts ◽  
Lateral Erosion

<p><span>Mantle plume-lithosphere interactions modulated by surface processes across extensional tectonic settings give rise to outstanding topographies and sedimentary basins. However, the nature of these interactions and the mechanisms through which they control the evolution of continental rifts are still elusive. Basal lithospheric shearing due to plume-related mantle flow leads to extensional lithospheric rupturing and associated magmatism, rock exhumation, and topographic uplift away from the plume axis by a distance inversely proportional to the lithospheric elastic thickness. When moisturized air encounters a topographic barrier, it rises, decompresses, and saturates, leading to enhanced erosion on the windward side of the uplifted terrain. Orographic precipitation and asymmetric erosional unloading facilitate strain localization and lithospheric rupturing on the wetter and more eroded side of an extensional system. This simple model is validated against petro-thermo-mechanical numerical experiments where a rheologically stratified lithosphere above a mantle plume is subject to fluvial erosion proportional to stream power during extension. These findings are consistent with Eocene mantle upwelling and flood basalts in Ethiopia synchronous with distal initiation of lithospheric stretching in the Red Sea and Gulf of Aden as well as asymmetric topography and slip along extensional structures where orography sets an erosional gradient in the Main Ethiopian Rift (MER). I conclude that, although inherently related to the lithosphere rheology, the evolution of continental rifts is even more seriously conditioned by the mantle and surface dynamics than previously thoughts.</span></p>

Reliability Analysis and Design for Pipe-in-Pipe Pipelines With Centralizers

2015 ◽  
Author(s):  
Steve Mao ◽  
Muhammad Kamal ◽  
Wei Qiao ◽  
Gang Dong ◽  
Brian Duffy
Keyword(s):  
Fatigue Life ◽  
Reliability Analysis ◽  
Fatigue Damage ◽  
Failure Probability ◽  
Probabilistic Method ◽  
Pipeline System ◽  
Limit Function ◽  
Analysis And Design ◽  
Manufacturing Tolerances ◽  
The Given

In this paper, a simplified reliability model is developed to identify how the pipe-in-pipe component uncertainties (manufacturing tolerances of centralizer thickness) influence the fatigue life of the system. The focus is on the reliability analysis with respect to the centralizer thickness. In order to reduce the complexity of the problem, only the centralizer thickness is considered to be a random variable. A limit function is formulated based on the three dimension (3D) finite element analysis. With the help of the probabilistic method, the correlation between the centralizer thickness and the failure probability is investigated. Two examples on pipe-in-pipe pipeline system are analyzed. The first one presents the relationship between centralizer thickness and failure probability for inner and outer pipes. The second one is an application of six mile pipe-in-pipe pipeline system. The failure probability of the fatigue is estimated. The influence of the centralizer thickness decreasing with time due to the abrasion, creep wear and elastic deformation is also considered when computing fatigue life and failure probability. The maximum fatigue damage ratio is calculated based on all trial samples generated considering manufacturing tolerances. If the maximum fatigue damage ratio is less than or equal to the allowable fatigue damage ratio, the failure probabilities with respect to the given centralizer thickness is negligible and the design is acceptable if only considering the influence of the given centralizer thickness. In addition, numerical results show that the maximum fatigue damage ratio possibly exceeds the allowable fatigue damage ratio considering manufacturing tolerances although the deterministic fatigue damage ratio is less than the allowable fatigue damage ratio.

Pipeline Safety Assessment at Inspection Time

2006 ◽  
Author(s):  
J. Alamilla ◽  
J. Garci´a-Vargas ◽  
J. Oliveros
Keyword(s):  
Failure Probability ◽  
Measurement Errors ◽  
Fluid Pressure ◽  
Corrosion Damage ◽  
Inspection Time ◽  
Pipeline System ◽  
Piping System ◽  
Pipeline Segment ◽  
Corrosion Defects ◽  
Pipeline Safety

This work presents a reliability model for determining the pipeline safety after obtaining information on the corrosion damage of the piping system by non-destructive inspection. The model is used to estimate pipeline system reliability in every region containing detected corrosion defects and the probability of either global system failure or of a given pipeline segment. The global failure probability incorporates the contribution of defects that are undetectable by the inspection tool. For this, the probability density functions of maximum depths and the number of undetected corrosion defects by the inspection tool are also determined. The failure associated to each corrosion defect is determined from the pipeline resistance and fluid pressure. The model is applied to a pipeline segment of a given length showing that defect measurement errors and the contribution of corrosion defects, undetected by inspection tool, can significantly influence the value of failure probability of the system. To calculate the failure probability of the system the directional simulation technique is utilized.

The Application of a Knowledge Transfer Taxonomy to Pipeline Construction Inspection Best Practices

2018 ◽  
Author(s):  
Ritch Rappel ◽  
Julian Dorscht ◽  
Reena Sahney
Keyword(s):  
Knowledge Transfer ◽  
Pipeline System ◽  
Specific Situation ◽  
Optimal Method ◽  
The Public ◽  
Knowledge Based ◽  
System A ◽  
Aging Infrastructure ◽  
High Level

The pipeline sector is facing a multi-faceted challenge regarding its workforce. Valuable knowledge is being lost as increasing numbers of technical experts and long-term employees exit the industry (due to retirement). Concurrently, the public spotlight is focused on the environmental impact of the pipeline industry. Therefore, robust construction of new pipelines and effective maintenance of aging infrastructure is increasingly important. Herein lies the challenge — How does the industry transfer the knowledge required to ensure that personnel have suitable competency to maintain the integrity of the pipeline system? A scenario where new personnel efficiently gain knowledge through experience is critical. An important aspect of achieving this is a more systematic and thoughtful approach to knowledge transfer. As part of its fundamental methodology for developing training and alternate methods for knowledge transfer, the team launched an initiative to review the literature and current industry approaches. This was done as a key input to developing a “Knowledge Taxonomy.” This tool simplifies the process for selecting the optimal method for effectively transferring key technical knowledge based on the desired level of competency (e.g., awareness building vs. mastery). Specifically, the team identified a number of consistent themes and combined them with both sound educational theory and industry experience to develop a tool in the form of a practical framework. This Knowledge Transfer Taxonomy was then applied to a specific knowledge gap in industry as a case study. This paper will 1. Summarize, at a high level, the results of the literature review and current approaches; 2. Describe the framework (i.e., Knowledge Taxonomy) developed by the team; 3. Discuss a case study involving the application of this framework to a specific and real challenge; and Through this work, the team identified and developed specific strategies and tactics to effectively overcome some of the barriers to knowledge transfer. These experiences will be shared in the context of a specific situation that typifies the current challenges industry is facing in effective knowledge transfer.

Reliability Analysis for Rotor System with Oil Whip and Resonance Based on Frequency

2012 ◽  
Vol 544 ◽  
pp. 110-114
Author(s):  
Chang Qing Su ◽  
Yi Min Zhang
Keyword(s):  
Failure Probability ◽  
Integration Method ◽  
Random Perturbation ◽  
Rotor System ◽  
Reliability Design ◽  
Rotor Systems ◽  
System A ◽  
Oil Whip ◽  
General Systems ◽  
Engineering Problems

Parameter uncertainty of general systems is inherent in most engineering problems. Based on the regularity of oil whip and resonance for rotor system, the reliability problem of rotor system with oil whip and resonance is studied by applying random perturbation technology and reliability theory considering the correlation of the multi-order natural frequency. The reliability mode and the failure probability of rotor systems are defined. The second-order joint failure probability is obtained by using the numerical integration method. The presented method provided the theoretic basis for the reliability design of the rotor system. A numerical example demonstrated that the proposed method is effective.

Toxicology and the Immune System: a Perspective

1991 ◽  
Vol 10 (6) ◽  
pp. 445-449 ◽  
Author(s):  
I. Kimber
Keyword(s):  
Immune System ◽  
Short Article ◽  
Comprehensive Account ◽  
System A ◽  
Recent Meeting ◽  
Remedial Work ◽  
Relationship Of ◽  
The Relationship

The relationship of immunology to toxicology has not always been an easy one, and the product of this association, immunotoxicology, has not infrequently been viewed with a certain scepticism by some of those who consider themselves 'classical' toxicologists. A recent meeting of the British Toxicology Society ('Toxicology and the Immune System', New College Oxford, March 21-22, 1991) provided an opportunity for some remedial work toward a wider appreciation of the issues which exercise immunotoxicologists, and the ways in which they are being addressed. It is not the purpose of this short article to provide a comprehensive account of the scientific presentations, but rather to give a perspective, necessarily a personal one, of immunotoxicology in the context of the meeting.

Investigation of Local Corrosion Degradation Developed on a Pipeline System in Service Period

2017 ◽  
Vol 885 ◽  
pp. 92-97 ◽  
Author(s):  
Peter Trampus ◽  
Enikő Réka Fábián ◽  
Zsolt Kerner ◽  
Magda Lakatos-Varsányi ◽  
László Péter ◽  
...  
Keyword(s):  
Power Plant ◽  
Nuclear Power Plant ◽  
Nuclear Power ◽  
Cooling System ◽  
Local Corrosion ◽  
Pipeline System ◽  
Spent Fuel ◽  
Comprehensive Investigation ◽  
System A ◽  
Service Period

Corrosion degradation was observed in a nuclear power plant spent fuel cooling system. A systematic and comprehensive investigation program was developed which was negatively influenced by the limit of sampling (contaminated material). Corrosion tests, mechanical and microstructural investigations were carried out and also microbiological effect was examined. Major contributors to the degradation were identified.

The Formal Adoption of a Process Safety Management Methodology Within an International Oil and Gas Pipeline Company

2012 ◽  
Author(s):  
Susan Urra
Keyword(s):  
Oil And Gas ◽  
Safety Management ◽  
Integrated Approach ◽  
Gas Pipeline ◽  
Pipeline System ◽  
Process Safety ◽  
Organizational Governance ◽  
Large Organization ◽  
System A ◽  
International Border

Process Safety Management (PSM) is an integrated approach to managing loss prevention. At Enbridge, as with many organizations, several PSM elements of practice have been implemented with different levels of rigor, maturity and/or alignment with best practices. This paper presents Enbridge Liquid Pipelines’ approach to assess a strategy to adopt a formal PSM system. A description of the current regulation framework for PSM and the drivers for adoption are presented to explain the considerations during the scoping and design of a PSM system for an international oil and gas pipeline system that operates across numerous state and provincial boundaries, and one international border. The paper also discusses the requirements for organizational governance to ensure accountability for and ownership of individual elements of a PSM program throughout a large, geographically diverse organization such as Enbridge. Finally, a strategy to develop and potentially implement and manage PSM in a large organization such as Enbridge is proposed.

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