Experimental Testing and Evaluation of Crack Defects in Line Pipe

2010 ◽  
Author(s):  
Ali Hosseini ◽  
Duane Cronin ◽  
Alan Plumtree ◽  
Richard Kania
Keyword(s):  
Experimental Testing ◽  
Assessment Methods ◽  
Narrow Slit ◽  
Line Pipe ◽  
Software Applications ◽  
Level 3 ◽  
Current Assessment ◽  
Different Depths ◽  
Welded Pipe ◽  
Elliptical Cracks

Pipelines are in wide use throughout the world, and aging pipelines may experience defects such as environmental or stress-induced cracking. The evaluation of crack defects is important for continued safe operation of pipelines. At present, there are several assessment methods for crack-like defects in pipelines including API579, BS 7910, NG18, software applications, as well as numerical modeling approaches. All have been used successfully to evaluate crack defects, but the degree of conservatism and sensitivity to the various input parameters is not known. To address this need, a series of full-scale burst tests was undertaken on end-capped, seam-welded pipe specimens. The tests were carried out on 508 mm (20 inch) diameter Grade API 5L X60 line pipe with a 5.7 mm wall thickness. Elliptical cracks were created by first cutting a longitudinally oriented narrow slit in each pipe and then pre-fatiguing the pipes to create sharp cracks of different depths. Rupture tests were conducted by pressurizing the pipes to failure and the failure pressure was evaluated using current assessment methods. Examination of the fracture surface showed that the pipe sections failed by ductile tearing, as expected for the material and crack sizes. It was found that the Level 3 FAD for API 579 (J approach, using the cylinder equations) and CorLAS provided the most accurate prediction in comparison with the other methods i.e. BS7910 and NG-18.

Development of X80M Line Pipe Steel for Spiral Welded Pipes With Low Temperature Toughness and Excellent Weldability

2014 ◽  
Author(s):  
Nuria Sanchez ◽  
Özlem E. Güngör ◽  
Martin Liebeherr ◽  
Nenad Ilić
Keyword(s):  
Low Temperature ◽  
Life Cycle Cost ◽  
Volume Fraction ◽  
Large Diameter ◽  
Pipe Production ◽  
Strain Accumulation ◽  
Long Distance ◽  
Line Pipe ◽  
Low Temperature Toughness ◽  
Welded Pipe

The unique combination of high strength and low temperature toughness on heavy wall thickness coils allows higher operating pressures in large diameter spiral welded pipes and could represent a 10% reduction in life cycle cost on long distance gas pipe lines. One of the current processing routes for these high thickness grades is the thermo-mechanical controlled processing (TMCP) route, which critically depends on the austenite conditioning during hot forming at specific temperature in relation to the aimed metallurgical mechanisms (recrystallization, strain accumulation, phase transformation). Detailed mechanical and microstructural characterization on selected coils and pipes corresponding to the X80M grade in 24 mm thickness reveals that effective grain size and distribution together with the through thickness gradient are key parameters to control in order to ensure the adequate toughness of the material. Studies on the softening behavior revealed that the grain coarsening in the mid-thickness is related to a decrease of strain accumulation during hot rolling. It was also observed a toughness detrimental effect with the increment of the volume fraction of M/A (martensite/retained austenite) in the middle thickness of the coils, related to the cooling practice. Finally, submerged arc weldability for spiral welded pipe manufacturing was evaluated on coil skelp in 24 mm thickness. The investigations revealed the suitability of the material for spiral welded pipe production, preserving the tensile properties and maintaining acceptable toughness values in the heat-affected zone. The present study revealed that the adequate chemical alloying selection and processing control provide enhanced low temperature toughness on pipes with excellent weldability formed from hot rolled coils X80 grade in 24 mm thickness produced at ArcelorMittal Bremen.

scholarly journals Assessing Sustainability in Housing LED Urban Regeneration: Insights from a Housing Association in Northern England

2019 ◽  
Author(s):  
Kevin Dean ◽  
Claudia Trillo
Keyword(s):  
Housing Association ◽  
Urban Regeneration ◽  
Assessment Methods ◽  
Costs And Benefits ◽  
High Rise ◽  
Current Assessment ◽  
Social Spillovers ◽  
The City ◽  
Regeneration Processes

How far do current assessment methods allow the thorough evaluation of sustainable urban regeneration? Would it be useful, to approach the evaluation of the environmental and social impacts of housing regeneration schemes, by making both hidden pitfalls and potentials explicit, and budgeting costs and benefits in the stakeholders’ perspective? The paper aims at answering these questions, by focusing on a case study located in the Manchester area, the City West Housing Trust, a nonprofit housing association. Drawing from extensive fieldwork and including several interviews with key experts from this housing association, the paper first attempts to monetize the environmental and social value of two extant projects – a high-rise housing estate and an environmentally-led program. It then discusses whether and how a stakeholder-oriented approach would allow more engagement of both current and potential funders in the projects at hand. Findings from both the literature and the empirical data that was gathered show how in current housing regeneration processes, room for significant improvements in terms of assessment methods still exist. Findings additionally show that the environmental and social spillovers are largely disregarded because of a gap in the evaluation tools. This may also hinder the potential contributions of further funders in the achievements of higher impacts in terms of sustainability.

Authentic Assessment as a Tool to Enhance Student Learning in a Higher Education Institution

2020 ◽  
pp. 256-271
Author(s):  
Abatihun Alehegn Sewagegn ◽  
Boitumelo Molebogeng Diale
Keyword(s):  
Higher Education ◽  
Real Life ◽  
Authentic Assessment ◽  
Education Institution ◽  
Assessment Methods ◽  
Assessment Practices ◽  
Higher Education Institution ◽  
Traditional Assessment ◽  
Qualitative Research Design ◽  
Current Assessment

Authentic assessment plays a great role in enhancing students' learning and makes them competent in their study area. Studies indicate that assessment is authentic when the tasks have real-life value and students perform real-world tasks. Therefore, this chapter shows how lecturers practice authentic assessment to enhance students' learning in a higher education institution. To achieve this, the authors used a phenomenological qualitative research design. An interview was used to collect data. The result indicated that lecturers are highly dependent upon traditional assessment methods, which have no significant contribution to the competency of students. The practice of authentic assessment methods as a tool to enhance students' learning is limited. Therefore, the authors can conclude that enhancing students' learning using authentic assessment in their study areas is untenable if the lecturers continue to utilize their current assessment practices.

A Comparative Analysis of Reliability Assessment Methods for Web-Based Software

2013 ◽  
Vol 1 (4) ◽  
pp. 31-44 ◽  
Author(s):  
Jinhee Park ◽  
Yeong-Seok Seo ◽  
Jongmoon Baik
Keyword(s):  
Service Oriented Architecture ◽  
Reliability Assessment ◽  
Dynamic Environment ◽  
Assessment Methods ◽  
Software Systems ◽  
Web Based ◽  
Software Applications ◽  
Web Environment ◽  
Service Oriented ◽  
The Web

As web technology has advanced, many business software applications are built on the web. In such web environment, it has become very important to ensure the reliabilities of web-based software systems such as Software as a Service (SaaS) or Service-Oriented Architecture (SOA) based systems because service failures in those systems may have an effect on extensive users. With the comparison to the reliability studies on traditional software, there are only a few studies on the reliability of web-based software. The dynamic environment of the web makes it much more complicated to assess the reliabilities of web-based software. In this paper, the authors investigate the characteristics of reliability assessment methods for web-based software such as SaaS and SOA based software systems. The authors also evaluate those methods based on hypothetical execution scenarios to analyze the strengths and weaknesses of each method. This analysis helps us to identify remaining problems on the reliability research in the web environment and provides insight into possible solutions.

New Technology Spiral SAW Pipes for Onshore and Offshore Oil and Gas Pipelines

2002 ◽  
Author(s):  
Josef Avagianos ◽  
Kostas Papamantellos
Keyword(s):  
Oil And Gas ◽  
Quality Management System ◽  
New Technology ◽  
Large Diameter ◽  
Production Capacity ◽  
Oil And Gas Industry ◽  
Step Method ◽  
Line Pipe ◽  
Water Transportation ◽  
Welded Pipe

The world production capacity on large-diameter welded pipe amounts to more than 12 million tons per year 20–25% are produced as spiral sub-arc welded (SAW) pipes, with the balance of 75–80% being longitudinal SAW pipes (from plates). For most spiral-weld producers, a sizeable portion of line pipe is for water transportation, rather than hydrocarbon. In the past, the relative structural weakness of spiral-welded pipe, due to larger welded area, limited the growth of its use in the oil industry. With the development of more advanced production technology, the acceptance of spiral-welded pipes in the oil and gas industry has increased significantly. In this paper, the principals of the spiral manufacturing technology from coil by the two-step-method are introduced and the innovations of Corinth Pipework’s production facility are outlined in detail, including the sophisticated NDT techniques and the Quality Management System.

Judge Me by My Size, Do You? How Reliable Are Dent Assessments Based on ILI Data?

2020 ◽  
Author(s):  
Rhett Dotson ◽  
Ryan Sager ◽  
Fernando Curiel ◽  
Marcus Le Roy
Keyword(s):  
Fatigue Life ◽  
Three Dimensional ◽  
Assessment Methods ◽  
Analytical Models ◽  
Remaining Life ◽  
Shape Factors ◽  
Assessment Guidelines ◽  
Current Assessment ◽  
Geometry Inspection ◽  
Dent Depth

Abstract Pipeline dents have historically been regulated and assessed using dent depth as the primary metric. Many of the earliest analytical models for dent remaining life are based upon depth. Current assessment guidelines from ASME and the Code of Federal Regulations utilize depth as a primary metric. Consequently, ILI geometry tool capabilities are stated in terms of dent depth. However, the best modern dent assessments, including both strain and fatigue assessments, are based on dent shape. At a minimum, these models require both axial and circumferential dent profiles, or the models may utilize the full three-dimensional shape of the dent. The utilization of advanced dent assessments is expected to grow in the future as the methods are incorporated into API Recommended Practices and US regulations. While operators may have confidence in the ability of an ILI tool to confidently capture the dent depth, the shape of a dent is a recent consideration that is not addressed by current tool specifications. Unlike depth alone, dent shape is often a function of sensor coverage, speed, and caliper technology. Unfortunately, there is virtually no information available on the reliability of these assessment methods when they are based on ILI data. To-date, there have been no published comparisons examining the variation in strain or fatigue life in identical dents between multiple inspections. The reliability of these dent assessment methods is critical when choosing safety factors or reinspection intervals. This study presents a first look at the repeatability of strain and remaining life assessments based on two separate geometry inspection using different technologies. The study examines dent strain according to ASME B31.8 and fatigue life calculated using shape factors and finite element methods for 257 dents. The paper examines the variation in each of the methods and provides guidance on how users should understand the results when they are based on a single geometry inspection.

A Comparative Analysis of Reliability Assessment Methods for Web-based Software

2013 ◽  
Vol 1 (3) ◽  
pp. 34-47 ◽  
Author(s):  
Jinhee Park ◽  
Yeong-Seok Seo ◽  
Jongmoon Baik
Keyword(s):  
Service Oriented Architecture ◽  
Reliability Assessment ◽  
Dynamic Environment ◽  
Assessment Methods ◽  
Software Systems ◽  
Web Based ◽  
Software Applications ◽  
Web Environment ◽  
Service Oriented ◽  
The Web

As web technology has advanced, many business software applications are built on the web. In such web environment, it has become very important to ensure the reliability of web-based software systems such as Software as a Service (SaaS) or Service-Oriented Architecture (SOA) based systems because service failures in those systems may have an effect on extensive users. With the comparison to the reliability studies on traditional software, there are only a few studies on the reliability of web-based software. The dynamic environment of the web makes it much more complicated to assess the reliability of web-based software. In this paper, the authors investigate the characteristics of reliability assessment methods for web-based software such as SaaS and SOA based software systems. The authors also evaluate those methods based on hypothetical execution scenarios to analyze the strengths and weaknesses of each method. This analysis helps the authors identify remaining problems on the reliability research in the web environment and provides insight into possible solutions.

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