Page 54 - Practical Design Ships and Floating Structures

Practical Design of Ships and Other Floating Structures 29
You-Sbeng Wu, Wei-Cheng Cui and Guo-Jun Zhou (Eds)
0 2001 Elsevier Science Ltd. All rights reserved

A CONSIDERATION OF LIFE CYCLE COST OF A SHIP

Yasushi Kumakura' and Hiroshi Sasajima'
' Kinki University, Japan
* Ishikawajima-Harima Heavy Industries Co.,Ltd. , Japan

ABSTRACT
In order to look all phases of a product life and to analyze the cost effectiveness elements, life cycle
cost of a product has been widely studied. In case of a ship, it consists of fabrication phase in shipyard,
such as design and fabrication, and maintenance phase in service, such as inspection, repair and
painting. So far life cycle cost of a ship has been calculated by the summation of fabrication cost and
maintenance cost by the end of her life. Although it is desirable to be able to estimate the life cycle
cost of a ship, when she is born in a shipyard, the estimation is very difficult due to the variety of
levels of fabrication and the maintenance. In this paper main items of fabrication cost and maintenance
cost of a VLCC are analyzed focusing in hull structure part, based on the actual data from shipyards
and ship owners and the relations between these costs are studied.

KEYWORDS
Life cycle cost, Design, Fabrication cost, Higher tensile strength steel, Steel structure, Maintenance
cost, Corrosion, Painting

1 INTRODUCTION

Ships are international commodities, which are freely sold and bought in the world. Ships are built in
shipyards with the highest shipbuilding technology in the world and delivered to ship owners. Some
ships are in service on the regular routes and others are in service on the irregular routes.

Transportation fees are decided in accordance with the laws of supply and demand of ships in the
world markets. In consequence all the prices, including those for ship building, running, maintenance
and selling to the other owners, are decided on these laws. With the participation of speculations these
prices show big scale of amplitudes.
In the heavy storms of economic situation there have been many speculators who bought ships, when
the prices of ships were at the bottom, made moderate maintenance on them and sold them to get big
amount of profits, when their prices sharply rose. They regard the ships as the objects of speculation.
However, during these economic fluctuations the prices of building and maintenance of ships are kept