Azimuth propulsion and unusual design features could set the standards for a new generation of chemical tankers
Two 15,000dwt oil products and chemical tankers have been ordered by the Turkish shipowner K.S. Tankers and incorporate a number of unusual design features which could set the standards for the new generation of chemical tankers. The Istanbul-based owner is having the 148m long vessels built at Cicek shipyard in Turkey, and plans to put them into service towards the end of 2004 and the second quarter 2005 respectively.
Designed by Delta Marine Design Bureau in Istanbul, KS Tankers has come up with a ship design that meets this demanding brief. With its double hull structure, clean sea notation, redundancy, ballast tank cleaning system features, the vessel meets the highest class authority requirements.
To be able to carry maximum cargo possible, the tanker company decided to use Marine Line coating in tanks offering a high level of resistance to almost all cargoes. The vessel's fine hull lines provide minimum resistance both from a hydrodynamic as well as an aerodynamic perspective.
Although these type IMO-II tankers will have ?clean sea? notation and Bureau Veritas ice class 1A so that it can operate in the Baltic all year round, they are intended to carry the maximum number of types of cargo, to work almost anywhere in the world, to comply with the highest standards of the oil majors and to go beyond the expectations of the classification societies.
Rolls-Royce is providing two Ulstein Aquamaster azimuth thrusters for main propulsion which will be powered by two 8 cylinder Bergen B32:40 medium speed diesel engines. Manoeuvrability will be aided by means of a Kamewa Ulstein 650kW tunnel bow thruster. The ship will also have an UMAS automation system which will monitor all machinery on the ships including tank sounding and cargo handling through active mimics on screen and work stations on the bridge and engine room. A set of Rauma Brattvaag high pressure hydraulic mooring winches, complete with remote control system are to be installed.
"This is the first time we have been asked to supply a complete equipment package for a tanker," says B?rge Nogva, sales manager for Rolls Royce in the merchant market sector. "The contract represents a breakthrough that I think will be noticed in the market."
It is also the first application of the Bergen B-series long stroke engine as main engines for a tanker, the order being won against strong competition. They will additionally be the first of the B32:40 type to burn heavy fuel oil, since others have been installed on offshore service vessels operating on distillate fuel. Each engine will develop 3,600kW at 720rpm.
The azimuth thrusters equipped with CP propellers will be directly coupled to the main engines, and at 85% MCR the vessel?s service speed fully laden will be 15 knots, burning about 24.5 tonnes of fuel per day. The main engines will drive two 1,200kW generators, with a small 125kW diesel genset in reserve.
Nogva notes that "It is unusual that the customer chooses azimuth thruster propulsion for this type of vessel. The reason is to improve manoeuvrability and to reduce the need for tug assistance in confined waterways and harbours. An added advantage is that the chosen propulsion system, with independent twin thrusters, provides full redundancy and emergency propulsion as well."
