Floating production, storage and offloading unit VARG

According to The Motor Ship November 1998

Turret-moored FPSO vessel built by Keppel Fels Singapore for the Varg Field in Norwegian sector of the North Sea. The 16 m-diameter turret is located forward of the midships area in order to provide a passive weathervaning capability. The turret bearing system has roller bearings above the main deck level to accommodate both vertical and horizontal forces. The turret is turned via a rack and pinion system driven by electric motors. As the wellstreams are manifolded at the nearby wellhead platform at the field, there is no manifold in the turret. Fluid and utility transfer between the turret and the ship is accomplished via a drag chain system based on tiers of armoured flexible hoses and cables arranged within a structure atop the turret. Hard piping connects each fixed end of the flexible to turret and to post on the vessel. This system allows the drag chain to wind and unwind around “0” mounted trolleys.

The process plant is capable of processing 13,000m3/day of liquids, and the production of 9000m3/day of oil and 9000m3/day of water respectively. The gas production and reinjection systems have a capacity of 1.5 million m3/day at 350 bar, while the capacity of the water injection system is 16,000m3/day at 230 bar. The process plant also comprises major systems such as the chemical injection equipment, a heating medium, cooling medium, sand removal equipment, and the fuel gas and flare gas system.

VARG has total storage capacity of 75,000m3 and two slop tanks. Crude is offloaded from VARG to tandem-moored shuttle tankers using deep-well pumps, at a rate of 4000m3/h, via the offloading arrangement.

Length, oa: 214.00m, Length, bp: 200.00m, Breadth, mld: 38.00m, Design draught; 16.00m, Deadweight approx. 100,000dwt.

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