Challenging Material and Fabrication Solutions for Deepwater Hydrocarbon Development

摘要

Materials and chemical technology advancements related to materials selection, corrosion mitigation/management, welding engineering and non destructive evaluation have enabled harsher service environments to be developed including, ultra deepwater field developments, sour and arctic conditions, high pressure/temperature, and high fatigue loading related to pipelines and steel catenary risers (SCRs). Reliable materials selection, fabrication and inspection techniques have the potential to save many millions of dollars on each project. Some of the reasons for this growing importance in materials engineering by the major operators include; 1. More material failures have recently been reported and may be attributed to poor materials selection, quality control and fabrication practice resulting in much higher repair cost and lost production. 2. Corrosion resistant alloys are being seen to give major long term benefits (OPEX), which are outweighing the short term higher capital costs (CAPEX) and an increasing awareness and concern for the environment and safety (HSE). This paper discusses subsea developments which demand high performance materials and coatings with characteristics such as adequate strength, flow assurance, resistance to the initiation of brittle fracture and fatigue, excellent weldability and protection against corrosion. Reference will be made to some offshore material failures, to illustrate the importance of the above factors and recommendations shall be given to avoid their re-occurrence.