Pipeline Design Philosophy and Standards – A comparative Study and Recommendations

CATEGORY: PIPELINES: DESIGN STANDARDS
Pipeline Design Philosophy and Standards – A comparative Study and Recommendations

Type	Conference Paper
Author	Nawin Singh
Author	Sajith Nair
URL	http://www.onepetro.org/doi/10.4043/26666-MS
Publisher	Offshore Technology Conference
Date	2016
Abstract	The most common method to transport oil and gas within the energy industry is through the pipeline transmission system. However, the pipeline system is very expensive, due to material and construction costs. One of the key decisive factors for a pipeline project is its capital expenditure (CAPEX). The material cost is primarily driven by linepipe cost, a function of pipeline size and thickness. Several pipeline design standards are followed worldwide based on either the Working Stress Design (WSD) or the Load and Resistance Factor Design (LRFD) approach. Authors present a comparative study and arrive at recommendations to optimize the material cost of linepipe, through a rational selection of the governing design code for pipelines, design philosophy and material grade. Traditionally, pipeline wall thickness is based on WSD, with the allowable design stress considered as a prescribed fraction of Specified Minimum Yield Strength (SMYS). However, there is inherent conservatism in the allowable stress method as only a certain fraction of material strength has been factored. A recognition of this conservatism by the industry resulted in the limit state approach. A detailed comparison has been performed of available international design standards and the approach followed worldwide to develop the matrix and perform the parametric study.