Float-over Installation

I-650 transport and launch barge effectively installs large integrated topsides up to 21,000-tons by float over, using a unique gravity-feed rapid ballast system, one of the fastest in the world. Its narrow bow accommodates most current float-over platform geometries, allowing it to enter jacket slots with ease, while its wide stern helps to maintain the barge’s integral stability, strength and loadout capacity.I-650 can transfer a 20,000-ton topside in approximately 20 minutes using its innovative rapid ballast system. The free-flooding system uses a series of large, remote-controlled valves located at the keel plate in eight different tanks, to ballast and lower the barge during topside weight transfer. Lowering speeds of 10 feet per hour for a deck-to-jacket float over have been achieved on projects in the field.

Driving float-over innovation is significant increase in topside weights, for shallow water platforms, deepwater Tension Leg Platforms and Semis. Impossible to lift in one piece, large topsides are built in modules, dramatically increasing offshore hook-up and commissioning time and costs. Above lift weights of 5,000 tons, suitable vessels to safely handle such installations are few and costly to mobilize. While name plate capacities exceeding 14,000 tons are advertised, a vessel’s geometry, hook reach and water-depth restrictions limit the ultimate lifting capacity. Derrick barges are sensitive to weather conditions and for a swell dominated offshore site, it is not unusual for a floating crane’s lift capacity to be de-rated 40-50%.