Riser Engineering
2H Offshore

Freestanding / Hybrid Risers

Hybrid tower riser

The Single Line Offset Riser (SLOR™) and the Concentric Offset Riser (COR) are 2H Offshore developed risers for deep water utilizing a freestanding steel section supported by a near surface air can.  The vertical section is connected to the production vessel by a short flexible jumper configured in a compliant catenary.

The SLOR can be either single pipe or pipe-in-pipe facilitating gas lift.  Designs of both systems are available for depths up to 3000m and these can be installed from a wide range of installation vessels including J-lay, reel lay and drilling vessels.

The SLOR is developed with full consideration to dynamic response, thermal requirements, hardware selection, installation, and field development flexibility.  A key feature is that it has low fatigue sensitivity and can be used with vessels which exhibit large dynamic motions and excursions.

The COR pipe-in-pipe arrangement is thermally efficient.  The annular space can be used for riser base gas lift allowing hot gas to be delivered to the riser base for injection to the production flow path with minimum complexity.

SLOR systems are being used for a range of services including production service and export.  Diameters up to 18 inches are possible with a single jumper and up to 30 inches with manifolded jumpers. 

The SLOR and COR are field proven on the Kizomba A and B fields connected to a spread moored FPSO.  An 18 inch export SLOR will be used by Petrobras on P52 in 2007 connected to a semisubmersible production vessel in 1800m.  Other major West African developments in depths up to 2000m are considering the SLOR as the base case solution for turret moored FPSO applications.