Anatomy of a SeaStar Installation

Anatomy of a SeaStar
Monocolumn Hull 1
  • Stiffened plate construction
  • Standard mild-grade, thin-plate steels
  • Fabricated in small modules
  • Assembled as complete unit at quayside
  • No hull penetrations below water line
  • No ballasting required during operation
  • Compartmentalized hull prevents flooding
  • Central moonpool is optional
  • Hull can be lengthened to increase payload
  • All compartments are accessible for inspection
Tendon Porches 2
  • Standard mild-grade, thin-plate steels
  • Integral part of hull structure
  • Support tendon top connectors, flex bearings, and tendon-load measuring instruments
  • Can be inspected externally and from inside the hull
Tendons 3
  • Tubular steel elements fabricated from well understood, high-yield materials
  • Multiple, mechanically coupled sections
  • 200 percent inspection with zero tolerance for material flaws
  • Design fatigue life typically exceeds 1000 years, well beyond the API-required 200 years
  • Tendon pairs have redundancy
  • Tendons are neutrally buoyant to improve hull efficiency
  • Fairings are installed on the tendons to prevent vortex-induced vibrations
Foundation 4
  • Three pairs of tubular steel piles positioned on the seafloor to match the position of tendons
  • Tendon receptacles are integrated into the tops of the foundation piles
Deck 5
  • Fabricated independent of hull
  • Conventional trussed deck structure
  • Leg spacing is conventional with four stabbing points
  • Deck and facility are commissioned onshore
Hull to Deck Transition 6
  • Tubular truss structure
  • Fabricated and outfitted independent of hull
  • Wave energy passes through the truss structure, minimizes wave loading on upper hull
Riser Porch 7
  • Hull framing supports catenary riser receptacles
  • Supports steel catenary production and export risers
Riser/Umbilical Pull Tubes 8
  • Tubular conductors (J-tubes) attached to hull
  • Flexible risers and umbilicals are routed through J-tubes for protection
Moonpool 9
  • Central access opening through center of hull
  • Accommodates an array of top-tensioned risers
  • Lower moonpool is fitted with a riser guide frame for lateral riser support
Production Risers 10
  • SeaStar TLPs accommodate both single and dual-casing, top-tensioned production risers
  • Production risers are tensioned at the deck
  • Fairings are installed on the risers to prevent vortex-induced vibrations