Lighter titanium translates into lower riser costs

Journal Article · Sun Sep 01 04:00:00 EDT 1996 · Petroleum Engineer International

OSTI ID:438963

Sauer, C W ^[1]; Actis, S C ^[2]; Thornton, J M ^[3]; Watkins, H B ^[4]

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1. Esso Norge AS, Stavanger (Norway)
2. Conoco, Lafayette, LA (United States)
3. Statoil, Stjoerdal (Norway)
4. RMI Titanium Co., Niles, OH (United States)

Titanium has been used previously in offshore oilfield applications for such things as platform piping, production tubing and casing. It has also been used in the manufacture of a production riser taper stress joint and a well intervention riser. But high strength titanium alloy has been used for the fabrication of only one drilling riser--a 22 in. ID, high-pressure riser for the Heidrun TLP in 1,132 ft of water. Titanium`s light weight helped reduce costs for the drilling riser system, the riser support deck structure and the associated riser handling equipment. The weight and tension requirements of a steel riser for the same application would have dictated the design of the interfacing equipment and structure and would have created an insurmountable problem with riser crossover and clashing between the drilling riser and the surrounding production risers. Titanium has many design characteristics that make it ideal for deepwater applications using existing equipment. It has a specific gravity of 4.54 g/cc, considerably less than steel`s 7.85 g/cc and oilfield grades of titanium have a minimum yield strength of 110 ksi. Steel used in the same applications has an 80 ksi yield. Easy to machine and weld, titanium exhibits a high degree of resistance to corrosive marine and produced fluid environments. The paper describes the Heidrun TLP experience, and drilling risers for deepwater applications.

• OSTI ID: 438963
• Journal Information: Petroleum Engineer International, Journal Name: Petroleum Engineer International Journal Issue: 9 Vol. 69; ISSN 0164-8322; ISSN PEEID4
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
42 ENGINEERING
BUILDING MATERIALS
CORROSION RESISTANCE
MARINE RISERS
MECHANICAL PROPERTIES
NORWAY
OFFSHORE PLATFORMS
PETROLEUM INDUSTRY
SPECIFICATIONS
TITANIUM
WEIGHT