- no.79, pp.xxxi-xxxvii, 1948
It has elapsed many years since the water tube boilers were introduced into marine use, with full success in European countries and in America. In Japan, on the contrary, this type of boiler has been used for some large cargo ships before the war and for a few kinds of War-time Standard Type of Ship under instruction of the former Japanese Navy during the war, but now no positive demands. It is generally recognized that through the possibility of high pressure and high temperature steam using the water tube boiler, the higher thermal efficiency and weight reduction in total engine part are gotten. This fact mokes us profitable to adopt the boiler in this country where fuel and steel are excessibly short. Nevertheless, there are hesitations in our ship world to adopt this type for marine boiler due to li anxiety of reliability and difficulty of handling. The problems on reliability and difficulty in handling. are as follows : (1) Danger of low water, (2) Trouble through feed water, (3) Easiness of coal burning. In this paper, the above problems should be investigated to clarify the reality, and if possible new design on the water tube boiler and finally the remedy to solve these problems will be protested.