Selection and evaluation of high strength steel for hutton TLP tension leg elements
The development of the tension leg platform (TLP) for the Hutton Field in the North Sea represents the first application of this deepwater concept. The use of vertical tension legs as the mooring system is the most novel part of the TLP design. One of the unique features of the tension legs is the use of 92.5-mm (3.64-in.) thick tubulars forged from 3 1/2 percent Ni-Cr-Mo-V high-strength steel (795 MPa (115.3 ksi) minimum yield strength) as mooring elements. Because of the importance of these elements to the survival of the TLP, the chemical composition and the steelmaking procedure were critically examined and optimized. In addition, extensive evaluation of the corrosion fatigue behavior of the steel was undertaken. This paper discusses the basis for the steel selection and specification, the results of the rigorous corrosion fatigue test program, and the assessment of the variation of properties along the length and through the thickness of full-size components. These results illustrate the suitability of the proposed high-strength steel for the mooring system application and establish confidence in both steelmaking and quality control procedures.
- Research Organization:
- Conoco Inc., Ponca City, OK
- OSTI ID:
- 6487628
- Journal Information:
- J. Energy Resour. Technol.; (United States), Journal Name: J. Energy Resour. Technol.; (United States) Vol. 106:1; ISSN JERTD
- Country of Publication:
- United States
- Language:
- English
Similar Records
Forged tubulars for tension leg platforms: material characteristics and fracture resistance in seawater environment
High reliability riser tensioners for the Hutton TLP
Related Subjects
360104 -- Metals & Alloys-- Physical Properties
42 ENGINEERING
423000* -- Engineering-- Marine Engineering-- (1980-)
ALLOYS
ATLANTIC OCEAN
CHEMICAL COMPOSITION
CHROMIUM ALLOYS
CONTROL
DEPTH
DESIGN
DIMENSIONS
FATIGUE
IRON ALLOYS
IRON BASE ALLOYS
LENGTH
MATERIALS TESTING
MECHANICAL PROPERTIES
METALLURGY
MOLYBDENUM ALLOYS
MOORINGS
NICKEL ALLOYS
NORTH SEA
OFFSHORE OPERATIONS
OFFSHORE PLATFORMS
OPTIMIZATION
QUALITY CONTROL
SEAS
SERVICE LIFE
STEELS
SURFACE WATERS
TESTING
THICKNESS
TUBES
VANADIUM ALLOYS
YIELD STRENGTH