Analysis of Unburied Pipeline Spans

ABSTRACT: Support requirements for unburied spans on existing pipelines can be difficult to assess. An approach for investigating the adequacy of support of unburied spans is presented. It begins with a screening based on theoretical longitudinal stress evaluation.  An estimate...

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Rational Stress Limits and Load Factors for Finite Element Analyses in Pipeline Applications Part II – Limit State Load Factor Development

ABSTRACT: In this paper, a load factor for use in a limit-load analysis of a pipeline and its      components is established. The load factor is based on the ASME pipeline Code’s design margin for the service and location of the installation . These...

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Elevated Temperature Primary Load Design Method Using Pseudo Elastic-Perfectly Plastic Model

ABSTRACT: A new primary load design method for elevated temperature service has been developed. Codification of the procedure in an ASME Boiler and Pressure Vessel Code, Section III Code Case is being pursued. The proposed primary load design method is intended to provide the same...

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One Power Plant’s Experience in Setting Up, Performing and Acting on a Pipe Hanger Surveillance Program

 ABSTRACT: The ASME B31.1 Power Piping Code, Chapter VII, has stated that Operating Companies shall establish a program to assess and document the condition of their Covered Piping Systems (CPS) especially those that operate in the creep range.  This includes maintaining design,...

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Application of Elastic-Perfectly Plastic Analysis to Assessment of Creep Strain

ABSTRACT: A cyclic elastic-perfectly plastic analysis method is proposed which provides a conservative estimate to cyclic creep strain accumulation within the ratchet boundary. The method is to check for ratcheting based on an elastic-perfectly material with a...

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Application of Shakedown Analysis to Evaluation of Creep-Fatigue Limits

ABSTRACT: Shakedown analysis may be used to provide a conservative estimate of local rupture and hence cyclic creep damage for use in a creep-fatigue assessment. The shakedown analysis is based on an elastic-perfectly plastic material with a temperature-dependent pseudo yield...

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Effects of Thermal Cycling on Offshore Pipeline Repair Tool Seal Systems

ABSTRACT This paper summarizes results from both coupon testing and full-scale testing directed at developing sealing systems to retrofit in traditional pipeline repair connectors and clamps so that they can undergo cycles of thermal heating and cooling without leakage....

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High Energy Piping Assessment Methods and Case Study

ABSTRACT: A comparison between analysis for piping design and analysis for piping assessment is given. Assessment requires consideration of high temperature failure modes such as girth weld cracking, hanger deflection issues and consequences of excessive cyclic loading.  Use of...

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Continuous Acoustic Emission (AE) Monitoring of a Known Flaw Site Behind a Nozzle Repad at Elevated Temperature

ABSTRACT: This paper discusses the application of AE as a method which provided an operator the feedback required to safely continue operation of a vessel with a through wall flaw. A vessel operator witnessed product leaking through the weep hole of a nozzle repad.  This...

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