In 2009 Heerema Marine Contractors awarded HFG the construction contract of 44 subsea structures for Phase 1 of BP Block 31 off the coast of Angola. The project consisted of two parts: the ITAs & FTAs and URAs & LRAs. The subsea structures were positioned at an average water depth of 2,000 meters. These highly-complex structures had to be constructed robust and according to extraordinary high-quality requirements, in order to withstand an extremely high pressure of 220 bar with a lifetime of at least 20 years.

FTA's are end pieces of a pipeline, while ITA's are tees in the middle of the pipeline. FTA's and ITA's monitor and control the production pipeline, and also provide the connection to the pipeline. The LRA provides the connection between the foundation on the seabed and the riser, an URA between the riser and the buoyancy tank.

Client:Heerema Marine Contractors B.V.
Contract type:Construction
Location:Offshore Angola
Structures:44 subsea structures
Project completion: 2011