Kawasaki's Double-Hull VLCC
The Ship 1618 is Kawasaki's first double-hull VLCC of 300,000-ton deadweight type. As the first one of the series ships for Golden Ocean Group which are to carry Panamanian flag, it was keel-laid in December 1998 and is scheduled for delivery in August 1999.
Features of the Ship
1. Principal Dimensions, etc.
The principal dimensions of the Ship including the gross tonnage are determined to secure as large a deadweight as 300,000 tons with a sufficient cargo capacity to carry more than 2,000,000 bbl of crude oil, aiming at the world's largest class ship of the best operational efficiency, which takes account of the compatibility with many VLCC terminals in the world including those in Japan. At a draft of about 20.1 meters, about 285,000-ton deadweight can be obtained; that is, such a hull form that can provide a necessary deadweight at a relatively shallow draft is adopted. Nonetheless, a high propulsion efficiency is maintained by optimizing the ship's lines and installing a rudder bulb with fins.
2. Hull Structure and Construction Method
Kawasaki's Apple Slot structure (patented, see figure) is applied to all the slot structures at connections between longitudinals and transverse webs where the fatigue strength is the most concerned factor in the hull structure; the Apple Slot is a drastically improved structure on the conventional one in such fatigue strength. Further, by large scaled fatigue analyses for such structures as bilge hoppers, as well as careful considerations to prevent vibration of the superstructure, struts in cargo tanks, etc., a highly reliable design of hull structure is attained.
As regards the construction method, such a block erection arrangement is adopted that the double hull part is divided into two at a center of the section (what is called "Nimai-Oroshi" which means "divided into two sections") for a better working environment.
