technical data and information between shiprepair yards or to unite technical power of all the bodies concerned in order to advance theories and techniques for assessment. repairing and maintenance.
3.3 Inadequate data and knowledge of hull structures of ageing ships
Considering the circumstances as mentioned in 3.2 and the following conditions, it should be admitted that we do not have enough data and knowledge of hull structures of ageing ships.
(1) It has not been required for design departments to collect data of ageing ships systematically nor to have the knowledge of ageing ships supposing the new themes coming up in future.
(2) A variety of shiprepair yards have had enormous experiences of repairing various kinds of ageing ships. But, the knowledge gained through these experiences has been hardly passed on to design departments or laboratories, and vital phenomena have tended to be overlooked or treated without analysis because of the usual practice in shiprepairing to restore damaged structures to their original conditions. The knowledge that is the outgrowth of the experiences with ageing ships may remain only as scrap in the heads of those who repaired them in the shiprepair yards.
(3) Classification societies have collected millions of data related to various items in the course of their long careers. But these data do not fully and automatically represent actual conditions of ageing hull structures. For example, records of thickness measurement are usually for the structures to be left as they are, so records without the data for deteriorated structures to be replaced cannot represent real status of the structures.
(4) There are some shipowners who are keenly interested in collecting technical data of their ships. But these data may not repesent the conditions of ships owned or operated by others.
3.4 Inadequate technical standards for hull structures of ageing ships
Though enhanced hull survey is being promoted and IMO has made utmost effort to exterminate substandard ships, regulations, manuals or guidelines pepared on the technical basis as mentioned above cannot be completely appropriate and adequate. More substantial standards for assessment, repairing and maintenance of hull structures of ageing ships are required.
