0

Full Content is available to subscribers

Subscribe/Learn More  >

Cost Effective Fabrication of Large Diameter High Strength Titanium Catenary Riser

[+] Author Affiliations
Agnes Marie Horn

Aker Kværner Technology AS, Oslo, Norway

Mons Hauge

Statoil, Trondheim, Norway

Per-Arne Ro̸stadsand

Aker Technology AS

Bjarne Bjo̸rnbakk

Vitec AS

Peer Dahlberg

Corrocean AS, Sandvika, Norway

Terje Fossesholm

Trelloborg Viking AS

Paper No. OMAE2002-28445, pp. 331-337; 7 pages
doi:10.1115/OMAE2002-28445
From:
  • ASME 2002 21st International Conference on Offshore Mechanics and Arctic Engineering
  • 21st International Conference on Offshore Mechanics and Arctic Engineering, Volume 3
  • Oslo, Norway, June 23–28, 2002
  • Conference Sponsors: Ocean, Offshore, and Arctic Engineering Division
  • ISBN: 0-7918-3613-4 | eISBN: 0-7918-3599-5
  • Copyright © 2002 by ASME

abstract

A large diameter high strength titanium free-hanging catenary riser was evaluated by the Demo 2000 Ti-Rise project, from initiative of the Kristin Field development license. In order to reduce the uncertainties related to the schedule, cost, and special technical issues identified in the work related to a similar riser for future installation on the Åsgard B semi-submersible platform, a fabrication qualification of a full scale riser in titanium was run. Several full-scale production girth welds were made in an in-situ fabrication environment. The welding was performed on extruded titanium grade 23 (ASTM) pipes with an ID of 25.5″) and wall thickness of 30 mm. The main challenge was to develop a highly productive TIG orbital welding procedure, which produced welds with as low pore content as possible. It is well known that sub-surface pores often are initiation sits for fatigue cracks in high strength titanium welds. This paper describes how a greatly improved productivity was obtained in combination with a high weld quality. NDT procedures were developed whit the main on the reliability to detect and locate possible sub-surface weld defects, volumetric defects such as pores and tungsten particles and planar defects such as lack of fusion. The results from the actual Non Destructive Testing (NDT), the mechanical testing, and the fatigue testing of the subjected welds are presented. The response of the catenary is optimised by varied distribution of weight coating along the riser’s length. A satisfactory weight coating with sufficient strength, bond strength, and wear properties was developed and qualified. The riser is planned to be fabricated from extruded titanium pipes, welded together onshore to one continuous piece. The field coating is added and the riser is loaded into the sea and towed offshore and installed.

Copyright © 2002 by ASME

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In