Maritime History of the Great Lakes

Marine Review (Cleveland, OH), March 1911, p. 99

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March, 1911 things about the matter is that the apparent temperature on the 35-lb. test, according to the electric pyro- meters, was 28 deg. higher in the third pass than in the second pass, whereas, on the 25-Ib. test it was 114 deg. low- er. Of course, these can represent only the local' temperatures at the points where the electric couples hap- pen to be placed--not the average "TAE Marine Review temperature of the entire body of gas in the two passes--and short circuits readily account for these apparent in- consistencies. "T am of the opinion that a coal of equal calorific value and having the same volatile characteristics, but free from the troublesome slag constituent, would have given higher efficiencies throughout the series." leavy Oil Engines for Marine Purposes By G. C. Davison.* INCE the time of Robert Fulton, a S period covering a century, the steam engine has been and is still general- _ ly considered the one practicable means, sails excepted, for the propulsion of ocean-going vessels. During this extensive period, the reciprocating en- gine has been developed to a point be- yond which no appreciable progress can be made. The steam turbine has been developed, but only under certain circumstances can it. exceed in econ- omy the reciprocating engine. Water- tube boilers have been developed and have also reached a practicable limit of efficiency. As a final step, oil has been introduced as fuel with water- tube boilers, so that today the most advanced steam motive power consists | of water-tube boilers, fired with liquid fuel, and turbine engines, together with a complicated mass of auxiliaries, such as feed pumps, blowers, air pumps, circulating pumps, etc. Stch installations are expensive from all points of view, first cost, attendance, fuel and repairs, so that practically we find them only on naval vessels where the utmost power on the least weight is demanded regardless of cost. Omit- ting the oil fuel feature, and substitut- ing coal, we find a few trans-Atlantic steamers, heavily subsidized, using the same modern steam system. But the remaining 99 and a fraction per cent of the world's merchant marine is pro- pelled by an installation consisting of coal burning boilers and recipro- cating engines. So much for what actually has been and is. As for what has 'been pro- posed, there may be mentioned the gasoline engine, which is prohibitive. due to the cost of gasoline; the use of light, high-speed turbines with elec- *Late Lieutenant Commander, United States navy. ideal OF gear transmissions, thus far but little more than paper propo- sitions, from which a certain amount of economy may be reasonably ex- pected, but which saving, when com- pared with that of the heavy oil en- gine, sinks into insignificance. The gas turbine, which has occupied the attention of able engineers and invent- ors for years, but for which practica- ble results are still: lacking. The producer gas plant which has been given scrious attention, but which up to date can use only anthracite coal, and for marine purposes has been in- stalled as an experiment on only a few small vessels. Use of Heavy Oil Engines. Of ail the proposed systems involv- ing internal combustion engines for marine purposes, the heavy oil engine, using high compression, has been the one which for years engineers have predicted success. These predictions have at last been realized, so that, at the present time, many thousands of horsepower derived from oil engines are used for the propulsion of vessels. All of the submarine bcats of the world, which have been built in the past few years, have been equipped with these engines, each boat having from 600 to 1,000 H. P. In addition, fishing vessels, tank steamers and tugs . in Europe have been equipped with these engines, and have been run long enough to fully demonstrate their practicability and economy. By far the greatest part of this development work has been done in Germany, the firm of Augsburg-Nurnberg having taken a leading part. In the United States, little progress has been made as re- egards heavy oil engines for marine purposes. The Diesel engine has been used with considerable success for sta- heavy . 99 tionary work. But for marine pur- poses, the only installation of heavy oil engines known are those in the submarine boats being built by the government. It is -:understood that a new concern, The New London Ship & Engine Co., has acquired the exclusive United States rights to the Nuremburg engine, and is preparing to 'build them for commercial pur- poses at its new plant in New Lon- don, Conn. The Nuremburg Type of Engine. A mere enumeration of the advant- ages of the heavy oil engine of the high-compression type, as represented by the Nuremburg engine, would fail to give an understanding of the possi- bilities of this motor, and of the far reaching effect which it is bound to have upon the problem of transporta- tion. Some time ago, Prof. Kokluns- ky, of Russia, after carefully investi- gating the subject, stated that "owing to dispensing with firemen, reduced fuel consumption and increased cargo capacity and passenger accommoda- tion, as compared with a steam vessel of the same size, 'the annual: gross earnings would be increased by 25 per cent, which would mean an in- crease of 8 per cent on the capital in- volved". But, fortunately, at the present time, we have some definite data in regard to the Hamburg-American ships now building, and from this information we can obtain a fairly approximate idea of the earning capacity which will be realized. The first of these vessels is of 7,000 tons displacement, is provided with two Nuremburg engines of the double- acting two-cycle type. Each engine developing 1,000 horsepower, has three working cylinders of 18.9 in. diameter, 25.6 in, stroke, and makes 120 revolu- tions per minute. The weight of the engines is about 88 Ib. per horsepower. To this must be added weight of shafting and pro- pellers, which will make the weight per horsepower about 100 Ib. On a steamer of the same size and power, the weight of boilers, engines, shaft- ing, piping and auxiliaries, will amount to 300 Ib. per horsepower. As regards fuel consumption, the Nuremburg engines are guaranteed to use less than one-half pound per horsepower hour. A steam vessel of the same class, when new might, on trial, use less than 2 1b. of coal per horsepower hour. But in practice, it is thought that an average consump- tion of 2 lb. per horsepower hour

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