Investigating offshore pipeline design via categorizing design stages and considering interaction of obtained hydraulic/material parameters with mechanical parameters

The aim of this article is to investigate the main stages of designing offshore oil/gas pipeline systems. To perform the work, design steps divided into three main categories including flow assurance, material selection and mechanical design. Then, main obtained data from each section such as internal diameter, wall thickness, material grade, maximumoperating pressure/temperature were specified. In order to optimize and finalize the calculated parameters, interactionbetween material selection and flow assurance sections with mechanical design section were considered. In this regard,particular attention on pipeline mechanical design sub-sections such as wall thickness calculation, stability calculation, thermal expansion, free span and pipeline installation analysis as well as riser and spool stress analysis was performed. In order to have better view about design stages and relevant interactions, a case study was run for 18 cladded infield offshore pipeline system located in phase1 of South Pars Field and obtained results were verified