Abstract

Titanium alloy Ti-6AI-4V ELI is selected for a high-pressure drilling riser application due to its high specific strength, corrosion resistance, and favorable elastic properties. The qualification of this titanium alloy requires assessing its resistance to hydrogen embrittlement and stress corrosion cracking due to seawater with/without cathodic protection, evaluating its wear resistance against a rotating steel drill string, and studying the influence of service-induced defects on fatigue and crack growth behavior when subjected to the operating environment. The paper presents an overview of the design requirements for a titanium drilling riser, and the material properties of the Ti-6AI-4V ELI alloy proposed for this application. The paper also highlights recent efforts to merge titanium and composite technologies to develop cost-effective drilling risers. [S0892-7219(00)01001-3]

Issue Section:
Technical Papers
Keywords:
oil technology, structural engineering, corrosion resistance, wear resistance, titanium alloys, design engineering
Topics:
Alloys, Design, Fatigue, Pipeline risers, Titanium, Titanium alloys, Wear resistance, Fracture (Materials), Seawater, Stress, Hydrogen embrittlement, Cathodic protection
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Copyright © 2000
 by ASME
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