SeawaysMPSS · offshore hosts, leased

The asset

What you are leasing

A bare hull. The structural platform, station-keeping provisions, basic marine systems and a defined set of interface points. Everything above the interface is yours.

The MPSS platform on station offshore: four square corner columns, full flat structural deck carrying topsides modules, mooring chains at each column.

Reference design

Specification

TypeMulti-Purpose Semi-Submersible — continuous submerged square ring pontoon, four square corner columns, full flat structural deck
Plan dimensions90 m × 90 m
Operating draft27.5 m
Deck top elevation56.25 m
Air gap to deck undersideSized so the deck sits clear above the operating waterline
Deck payload envelope30,000 t
ConstructionFlat stiffened plate and box-girder throughout. No diagonal bracing, no tubular nodes
Station keepingMoored. Fairlead and chain locker foundations at fixed locations, sized to a defined load envelope
BallastCompartmented ring pontoon plus column tanks. Sequenced pontoon first, then column tanks from the bottom upward
Riser capabilitySuitable for steel catenary risers where the application calls for them
Structural life40 years

Reference design figures. Site-specific metocean qualification is confirmed per deployment.

The interface

Fixed so it can be leased. Open so it can be used.

A leasable hull only works if the things that govern qualification are frozen, and the things that govern your business are not.

Fixed across every hull

  • Column size and spacing, ring-pontoon geometry, operating draft — these set the motion characteristics and cannot vary without re-qualification
  • Primary structural scantlings, weld details and fabrication sequence
  • Deck grid and load-out interface points, with defined load capacities
  • Mooring and station-keeping foundation points

Yours to determine

  • Topsides modules and their internal layout — entirely your scope
  • Riser porch fit-out, where the porch is a standard interface and the riser hardware is yours
  • Utility tie-in capacity for power, cooling water and data, provisioned as spare capacity and activated as you need it
  • How much of the payload envelope you take — lighter applications simply use less of it
The hull is the commodity. The topsides are the differentiator. You should own the part that differentiates you and lease the part that does not.

Risk position

Not a new hull form

In service now

Ring-pontoon, four-column, deep-draft platforms are the standard deepwater production host in operation today, carrying hydrocarbons in the most demanding motion environments offshore.

A known class pathway

Class societies have approved this hull form repeatedly for other owners. Unit certification proceeds on build in the normal way, against a form the societies already know.

Pre-certified design

Lloyd's Register pre-certification, an independent hazard review that identified no inherent safety weakness, and physical model testing of structure and hydrodynamics at the University of Glasgow.

Primary documentation is released to qualified counterparties under NDA. Site-specific qualification and unit class certification are normal build-stage activities, not open questions about the architecture.

How the lease works → What goes on the deck