Kaombo HPU Skid Frame
Offshore of Angolan Coast – South Atlantic Ocean
Technicus Consulting were appointed by Specialised Management Services (SMS) to provide structural design services for a 31Te stainless steel Hydraulic Power Unit (HPU) Skid Frame. The HPU is to be installed on a Floating Offshore Storage & Offloading (FPSO) vessel located off the West coast of Africa.
The unit required designing for 4-point, 2-point and fork-lifting in accordance with DNV 2.7-3 along with operational case design for blast loads of 0.27bar (27kN/m2) and vessel motion acceleration loads.
Additional to the design of the primary skid frame structure, Technicus were also appointed to design the 10,000 litre capacity hydraulic fluid reservoir installed within the unit. This was to be designed for vessel acceleration and hydrodynamic forces only as the primary HPU structure protects the reservoir from blast forces.
The blast design specification for the HPU stated that the skid frame must remain intact, but not operational following exposure to a blast event. Consequently, permanent deformation of the cladding and primary structural frame under blast load conditions would be acceptable.
The operational and blast case designs required the partial modelling of a portion of the FPSO Turret Deck in order to assess the effects of overall deck deflections on the installed HPU Skid Frame and its holding-down bolt fixings.
The resulting designed structure, although heavier than a standard duty skid frame, has produced an efficient structure capable of resisting environmental and blast forces associated with the Kaombo FPSO vessel.