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WÄRTSILÄ
Encyclopedia of Marine and Energy Technology

Pelagic freezer trawler AFRIKA

marine

According to HSB International April 1999

The pelagic freezer stern trawler AFRIKA is designed to operate in the tropics, fishing mainly for sardinella and horse mackerel. Built by YVC Ysselweft the 6400dwt vessel has an overall length of 126.20m and a beam of 17.50m. It has a long foredeck with the superstructure close to the stern, leaving a trawl deck aft of the wheelhouse.

Fishing gear is handled over the stern using the giant trawl winch supplied by Brusselle Marine Industries driven by two Bakker Sliedrecht 350kW electromotors. The eight-drum trawl winch has two shaft lines. The lower shaft carries two main drums, each for 4000m of 40mm diameter steel wire rope, two auxiliary drums, each for 83m of 32mm diameter steel wire rope and one net drum having a net capacity of 20m3 . The two main drums are provided with an automatic wire-rope reeling system of the cross-spindle type. The nominal total pull on main drum 11th  layer is 510kN at 0-72m/min with a brake force of 660kN.

The upper shaft carries two auxiliary drums, each for 83m of 32mm diameter steel wire rope, and one net drum having a net capacity of 20m3.

The eight drums, arranged on two sectional shaft lines, are carried by roller bearings with central gearcase. An automatic lubrication device is provided for reaching all the moving parts.

Deck operations are controlled from a console at the back of the wheelhouse with a full view over the deck. All of the winches are operated from this position.

The AFRIKA has no stern ramp. Once the fish is caught and the net is hauled in, the catch is transferred into Refrigerated Sea Water (RSW) tanks with a large submersible fish pump handled by a hydraulic crane. The fish pump has a capacity of 250 tons per hour (1400 mfish/water per hour) and transfers the fish from the net to the fish bins from where it is immediately discharged through hatches into twelve RSW tanks where the fish is pre-cooled.

Subsequently, the fish is vacuum-pumped with a fish pumping system to the sorting belt and to six cooled sorting bins, from where it is pumped to a conveyor system leading to 40 vertical plate freezers. After having been frozen to a temperature of minus 25°C, the fish blocks, weighing about 25 kg each, are sealed in sealing machines and then packed into cardboard boxes and stowed in refrigerated holds.

The handling equipment to transport the fish from the packing station to the fish holds consists of horizontal and vertical conveyor systems. The holds of the vessel are fully equipped for palletized cargo to be discharged by forklift trucks to the hatches and from there landed with shore cranes.

Length o.a.: 126.22m, Length b.p.: 118.99m, Breadth, mld: 17.50m, Depth, mld: 11.02m,

Draught: 6.85m, Deadweight: 5977dwt, Speed: 17.6knots, MCR: 7210kW.