The Thunder Horse subsea development comprises of four (4) drill centers tied back to a semi-submersible Processing, Drilling and Quarters facilitiy (PDQ). This semi-submersible PDQ is taut wire moored in approximately 2000 meters water depth directly above the main drill center DC41, and has a processing capacity of 250 mbd of oil and 250 mmscfd of Gas.

The pre-lay of the moorings as well as connection to the semi PDQ and the subsequent installation of the Mardi Gras Export Risers were carried out under a separate Contract by the Balder in Q3/4 2004.

First oil was scheduled for May 2006. The Thunder Horse subsea contract scope involved:

  • 22 km of production and test flowlines (8 flowlines)
  • 20 km of production and test Steel Catenary Risers (5 SCR's)
  • 2 large manifolds of 300 short tons each, with suction pile foundation
  • 2 smaller manifolds of 150 short tons each, with suction pile foundation
  • 13 PLET walking anchors
  • 18ft diameter hold back anchors (suction piles)
  • 21 Pipeline End Terminations (PLET)

All production and test flowlines and risers are 8, 10 and 12 inch in diameter and coated with upto 4 inch thick multi-layer Thermal Insulation Coating. Flowlines have a wall thickness of 30 to 35 mm. Risers have a wall thickness of 35 to 40 mm.

This was the first development that fully utilized our Deep Water Construction Vessel Balder; with mooring lines, suction piles, manifolds, export pipelines, insulation coated infield flowlines, steel catenary risers and PLET's and PLEM's in its scope.

Main Characteristics

Offshore Start Date: 2004-Q1
Offshore End Date: 2006-Q4

Main Spread
Vessel: --
Transport Vessel(s): Balder
Hamers: --

Main Technical Data
Flowlines: OD: 8.62 - 12.75"/ Wall Thickness 30 - 38mm / Thermal Insulation 2.98-3.72"
Risers: OD: 8.63 - 12.75"/ Wall Thickness 33.8 - 40 mm / Thermal Insulation 1.97-2.76"