Marine Engineer and Motorship Builder, Volume 121891 - Marine engineering |
Other editions - View all
Common terms and phrases
2C London 2C N.Shields A1 at Lloyd's accommodation Admiralty arrangements boats boilers breadth builders built by Messrs bulkhead Canal Captain Cardiff cargo carried cent Clyde coal constructed cruisers cylinders deadweight depth diameter dimensions:-Length dynamo engine-room engined by Messrs evaporator exhibits firm first-class fitted forced draught forecastle furnaces Glasgow Greenock guns Hartlepool heat hour hull iron launched Leith length Limited Liverpool Lloyd's load machinery Manchester Manchester Ship Canal manganese bronze marine engineering measured mile month moulded Naval Navigation order of Messrs owners paddle steamer passengers patent piston plates poop port present pressure propeller pumps Railway revolutions per minute sailing saloon shaft ship shipbuilding yard South Shields square inch steam steering gear steam winches steam windlass Steamship steel screw steamer stroke Sunderland supplied surface surface condensing temperature tonnage tons trial trip triple-expansion engines tubes twin-screw valve vessel West Hartlepool windlass yard of Messrs
Popular passages
Page 198 - ... per cent, in cargoes under 500 tons ; in cargoes from 500 to 1000, I per cent. ; 1000 to 1500, to 3'5 per cent. ; 1500 to 2000. to 4-5 per cent. ; and over 2000 tons, to no less than 9 per cent. Mass influences this action in two ways : — (a) The larger the cargo, the more non-conducting material will there be between the spot at which heating is taking place and the cooling influence of the outer air. (b) The larger the cargo the greater will be the breaking-down action of the impact of coal...
Page 198 - This startling result is partly due to the length of time the cargo is in the vessel, the absorption and oxidation being a comparatively long action ; but a far more active cause is the increase of temperature in the tropics, which converts slow action into a rapid one.
Page 198 - ... There is great diversity of opinion on this point, but it is pretty generally admitted that cases of heating and ignition are more frequent in coals shipped from east coast ports than in South Wales shipments. So much, however, depends upon the quantity of small coal present, that a well-loaded cargo of any coal would be safer than a cargo of Welsh steam coal in which a quantity of dust had been produced during loading. 4. The size of the coal (small coal being much more liable to spontaneous...
Page 199 - Oliver Cromwell, Calcutta, and Corah, which ' were loaded at Newcastle under the same tips, at the same time, with the same coal, from the same seam. ! The first three were bound for Aden, and were all ventilated. The Corah was bound for Bombay, and was not ventilated. The three thoroughly ventilated ships were totally lost from spontaneous ignition of their cargo, whilst the Corah reached Bombay in safety. Prof. Lewes points out that for ventilation to do any good, cool air would have to sweep continuously...
Page 200 - ... of any boiler, furnace, or bench of retorts. No coal should be stored or shipped to distant ports until at least a month has elapsed since it was brought to the surface. Every care should be taken during loading or storing to prevent breaking or crushing of the coal, and on no account must a large accumulation of small coal be allowed. These precautions, if properly carried out, would amply suffice to entirely do away with spontaneous ignition in stored coal on land.
Page 98 - So that no stretch of imagination could endow the small trace of pyrites scattered through a large mass of coal, and undergoing slow oxidation, with the power of reaching the needful temperature.
Page 198 - ... 3. The kind of coal of which the cargo consists (some coals being specially liable to spontaneous heating and ignition). — There is great diversity of opinion on this point, but it is pretty generally admitted that cases of heating and ignition are more frequent in coals shipped from east coast ports than in South Wales shipments. So much, however, depends upon the quantity of small coal present, that a well-loaded cargo of any coal would be safer than a cargo of Welsh steam coal in which a...
Page 200 - ... fuel. These objections weighed so strongly with the Commissioners that in their final report we find the following sentences : — " Several methods for generating carbonic acid gas and applying it to the ignited portion of a coal cargo have been proposed for our consideration. We consider, however, that although this gas might be useful by excluding atmospheric air (which is essential to support combustion), yet it will not, as water does, exert any very sensible cooling effect, which is a point...
Page 199 - ... in coal cargoes — whilst anything short of that only increases the danger — the ordinary methods of ventilation supplying just about the right amount of air to create the maximum amount of heating. The reason of this is clear. A steam coal absorbs about twice its own volume of oxygen, and takes...
Page 14 - The vessel moved delightfully, and, notwithstanding the smallness of the cylinders (4in. in diameter), went at the rate of five miles an hour. It continued to ply for some days for the amusement of the projector, and to the astonishment of the country people, who assembled from all quarters to witness the wonders of a "boat driven by reek.