Hotpipe Project: Design Guideline For High Temperature/High Pressure Pipelines

Recent development plans envisage the transport of hydrocarbons at temperature and pressure conditions far more severe than in past projects. Indeed, technical feasibility of certain inter field lines was put in doubt as a consequence of application of design guidelines currently in force. This fact gave rise to a critical review of design criteria. Statoil and Norske Agip have sponsored an R&DHOTPIPE project whose overall objective is to prepare a DNV Recommended Practice, to be used in the verification and design of high temperature/high pressure pipelines. The design guideline covers most practical cases where pipelines are subjected to high internal pressure and temperature. The design criteria are based on the application of reliability methods to calibrate the partial safety factors involved. This paper describes the main structure of the design guideline, focusing on pipeline scenarios and design procedures. Further, draft design criteria for handling snaking of a pipeline on a flat seabed are given for illustration.