Development, pre-qualification, and production history of 60 ksi UOE steel tendon pipe for AUGER tension leg platform

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:205424

Takeuchi, Izumi; Nishimoto, Koji; Nagase, Makoto; Nishizawa, Masashi ^[1]; Smith, J D; Bowen, K G ^[2]

---

1. Sumitomo Metal Industries, Ltd., Kashima (Japan)
2. Shell Offshore Inc., Houston, TX (United States)

AUGER Tension Leg Platform (TLP) tendons consisted of specially designed threaded forged connections welded to thick-walled tubular tendon segments. This paper describes the development, pre-qualification testing, and production properties of the 60ksi-26 in. O.D. x 1.300 in. wall-thickness steel pipes which formed the TLP tendon segments. The tendon pipe segments were manufactured by the UOE process using Thermo-Mechanical Control Process (TMCP) steel plate with double-submerged arc seam welding (DSAW). Stringent mechanical properties and dimensional control requirements were established for the tendon pipes, with special emphasis on weldability and resulting high heat-affected-zone (HAZ) crack-tip opening displacement (CTOD) fracture toughness. The weldability (hydrogen delayed cracking resistance) and fracture toughness of the HAZ showed high and stable performance. Tight dimensional control, especially ovality, ensured minimal high-low during the making of girth welds at the construction site. Limiting high-low is an important parameter for lowering local stress-concentration factor (SCF) and increasing fatigue life. These results are discussed with particular reference to the steel Local Brittle Zone (LBZ) concept. Narrow range control of the TMCP steel chemistry, plate manufacturing process, and UOE pipe-forming and seam-welding process insured that all requirements were met for the production quantity.

• OSTI ID: 205424
• Report Number(s): CONF-950695--; ISBN 0-7918-1309-6
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
FRACTURE MECHANICS
GULF OF MEXICO
MATERIALS TESTING
MECHANICAL TESTS
OFFSHORE PLATFORMS
STEELS
SUPPORTS
WELDABILITY
WELDED JOINTS