The Belleville Boiler
Text from Jane's Fighting Ships, 1906 - 07 ed., 464.
The Belleville boiler is the most used of all the various types of water-tube boiler in the War Navies of the world, and there has been accordingly been great experience with it, with the result that it is to-day the most economical and serviceable boiler afloat. It consists of a series of elements arranged side by side, each element being formed by two vertical rows of parallel tubes inclined in opposite directions at about 3° from the horizontal. The tubes of these two rows are united by horizontal junction boxes, and each element is connected to the steam drum at the top by a flange joint, and to a square horizontal tube (known as the feed collector) at the bottom by a conical nipple joint.
Above the main portion of the boiler proper is a smaller copy of it known as the economiser, consisting of similar elements of rather smaller tubes, and the space between them forms a second combustion chamber. The feed water delivered by the feed pump passes through a regulating valve on the automatic feed regulator shown at the front of the boiler. It then passes into a distributing box at the bottom of the economiser, through the elements to the outlet at the top, and is led to a non-return valve fixed on the steam drum, along which latter it flows, finally passing down to the feed collector, and so into the elements which form the boiler proper.
The arrangement of the boiler in two parts as shewn is very conducive to the efficiency of combustion, and the feeding arrangements are such that the circulation is certain and constant.
As the premier water-tube boiler of pre-dreadnought times, Bellevilles achieved acceptance second only to the Scotch fire-tube boiler that preceded them. A range of competing models emerged soon after the turn of the century, with Babcock perhaps being the longest lived. But Belleville's position of dominance at the apex of the pre-dreadnought era ensured its contribution to a roster of illustrious warships of the period. Witness the ones below. -- Ed.
The USS Brooklyn, soon to be the victorious U.S. flagship at Santiago, on trials in 1896. Uniquely in the American fleet, she emulated French "fierce face" design characteristics such as extreme verticality and tumble-home hull shape. Brooklyn was rebuilt in 1909 - 11 with conventional cylindrical boilers. Historic Profile
Most distinguished of the Belleville-boilered fraternity was the Japanese flagship Mikasa, built by Vickers in 1899 - 1902. Nearly identical to the British London class, her derivation from the Majestic and Canopus classes is obvious to even the casual eye.
