Wartsila Delivers Combination Tanker xTavi' To Neste Oy
The Turku shipyard of Oy Wartsila Ab recently completed the 19,999-dwt crude oil/chemical/ products tanker Tavi (shown above), first of two ordered by Neste Oy, the Finnish national oil company. The vessel was delivered less than 14 months after keel-laying. The Tavi is built to Lloyd's Register of Shipping classification +100 Al, Chemical Tanker, +LMC, UMS, IGS, Ice Class 1A. She is an IMO type II/III chemical tanker for worldwide trading of crude oil, oil products, and type II/III chemicals including benzene, styrene nonomer, caustic soda, caustic potaska, molasses, urea, white spirits, solvents, and alcohol. The cargo list comprises 72 different chemicals most widely transported by sea. The tanker has an overall length of about 528 feet, beam of 76 feet, depth to upper deck of 46 Vi feet, and design draft of 33 feet. Propulsion is provided by a Wartsila/Pielstick 6PC4.2L-570 diesel engine coupled through a reduction gear to a KaMeWa controllable-pitch propeller. The engine has a maximum continuous output of 9,776 bhp at 400 rpm. The ship is also fitted with controllable-pitch bow thruster driven by a 1,000-kw electric motor. Three Wartsila-Vasa 6R22HF auxiliary diesels are direct-coupled u> Stromberg 935-kva alternators.
Main and auxiliary engines, boilers, and inert gas generator are all able to run with one kind of fuel on board—3,500 sec Redwood at 100 F.
The hull is divided, by two longitudinal and 11 transverse bulkheads, into 10 center tanks and eight side tanks for cargo, six side tanks for water ballast, and two slop tanks. Transverse bulkheads are stiffened by corrugating; longitudinal bulkheads are smooth in the center tanks with stiffeners in the side tanks. Center tanks are coated with pure epoxy; cargo side tanks are coated with zinc silicate.
Each cargo tank is fitted with a Thune Eureka deepwell pump. For cargo heating, 18 Sunrod heaters are installed on the main deck. One Maritime Protection inert gas generator is installed in a deckhouse aft. The generator has a capacity of 3,300 cubic meters per hour with a maximum pressure of 0.2 bar.
Despite being a ship less than 150 meters (492 feet) and of less than 20,000 dwt, the design of the Tavi incorporates some of the more severe requirements applicable to larger vessels. These include damage stability, segregated ballast water tanks, crude oil washing, and the inert gas system.