Offshore Pipeline Free Spanning Analysis Based On DNV Design Code

• Main Author: Mohd Hanifa, Hazlinda
• Format: Final Year Project
• Language: English
• Published: Universiti Teknologi Petronas 2008
• Subjects: TA Engineering (General). Civil engineering (General)
• Online Access: http://utpedia.utp.edu.my/id/eprint/7335/1/2008%20-%20Offshore%20pipeline%20free%20spanning%20analysis%20based%20on%20DNV%20design%20code.pdf; http://utpedia.utp.edu.my/id/eprint/7335/

Offshore pipeline has proven the most economical means of large scale transportation method for crude oil, natural gas, and their products for oil and gas exploration. Problems faced during pipeline mechanical design is free span formation due to seabed unevenness, scouring action, and exposure to current and wave flow. 1bis work presents proper free span assessment to avoid excessive loads and deformation as pipeline could undergo oscillatory force, excessive bending stresses, and buckling. Analysis spreadsheets were created for free span analysis according to latest Det Norske Veritas (DNV) design codes; DNV-RP-Fl05 "Free Spanning Pipelines, February 2006". Results obtained were presented in graphs and tables. Parametric studies were performed to determine the span length for different outside diameter, safety factor and boundary condition. Results indicated that pipeline failure occurred if span length is longer than the permitted length. 1bis can be solved by rerouting, span correction, installation of grout bag support or mattresses.