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'THE Marine REVIEW : gi contracts for the construction of two large vessels to be equipped with twin independent Curtis turbines, which vessels, together with the turbines, the Fore River Com- pany is now building. One of these is the U. S. scout cruiser Salem and the other is the Southern Pacific steam- er Creole, particulars of which are as follows. Salem. Creole.' TOW, Bere ae. 420 ft.o inches 415 ft. 8 inches Breadth 20000. 46 ft. 8 inches 53 ft. 0 inches MOTHBONT eas ck 16 ft. 9% in. 25 ft. o inches Displacement: <. a6. occ. 3,750 10,160 tons ;: FrOtse- power ©... .<... 16,000 8,000 Speed (vie 24 knots 16 knots In both vessels there are two shafts and two screws with complete independent turbines on each shaft, In the case of the Salem the proposed revolution of. the screw at 24 knots is 350; in the case of the Creole somewhere between 225 and 275. The space occupied by the turbines fore and aft (including the reversing mechanism) is only about half that occupied by the equivalent triple or quad- ruple expansion four cylinder engine and the weight is considerably less. In the case of the Creole the weight of the two turbines is, roughly speaking, about half of that of the equivalent quadruple expansion engine. The total saving in weight of the engines, shafting, propellers, etc., is very considerable. Each turbine is in the form of: a drum shaped shell, built up in sections, having an outside diameter of about 11 ft. and an over all length of about 14 ft. Each turbine comprises 7 stages for going ahead and two stages for reversing. There is no end thrust due to the pressure of the steam in the turbine itself and the propeller thrust is taken up by the ordinary thrust block external to the turbine. During the past summer the Vulcan Shipbuilding Com- pany of Germany completed a turbine vessel called the Kaiser, which is fitted with two shafts and two indepen- dent turbines of this type. _The turbines were built for the Vulcan Works by the Algemeine Eliktricitats Gessellschaft of Berlin, who are licensees under the Curtis Turbine Patents, and were designed by and built under the very able direction of Mr. O. Lasche, the technical director of the turbine works of the Allgemeine Company. The performance of these turbines and of the vessel on her trial trip was admirable, and reflects great credit upon Mr. Lasche and his associates, and also the, designing engin- cers of the Vulcan Works, who assumed the responsibility of getting efficient screw action under the unusual condi- tions. The guarantees were intended to represent the performance of a first class 4-cylinder triple, expansion engine and the ordinary slow turning screws which neces- sarily have a somewhat higher efficiency than the compa- ratively high revolution screws requisite for turbine pro- pulsion. The actual figures guaranteed were a speed of 19% knots, and a consumption during a 6-hour run of not over 4,700 kgs. of coal per hour, including all auxiliaries. Progressive speed trials were had up to 20.46 knots, the propellers turning at 655 revolutions per minute. During a 6-hour run 20 knots averaged on 4,060 kgs. of coal per hour. We have not yet ascertained positively what the H. P. developed was, but we understand that the shaft H. P. was measured by the use of a torsion shaft, and we un- derstand on good authority that the indicated H. P. of the engines for the ship at 20 knots is estimated at 5,700. Whether this is derived from the shaft H. P. measurement or confirmed by the shaft H. P. measurement we do not as yet know. But if this figure--s,700 I. H. P.--sent to us is correct, the coal works out at 1.56 pounds per I. HP, including all auxiliaries. The coal result is, if anything, better than these figures show, for during two hours the 'safety valves were blowing and the steam by-passing to 'the condensers. On a basis of the cube of the speeds the H. P. at 20 knots would be 8 percent greater than that at 19% knots, and as the coal consumed at 20 knots was only .864 percent of that guaranteed for 19. knots, it would appear that at a speed of 19 knots the coal consumption would be just 80 percent of the amount guaranteed. The dimensions of the vessel are as follows: Water line length, 310 ft. Beam, 38.2 ft. Draught on trial trip, 9.74 ft: Displacement, 1,890 tons of 2,240 pounds. : In order to test the manoeuvering and backing uakties of the turbines, which were entirely independent, another engine driven vessel belonging to the same line (the Ham- burg Line) was brought to the spot for comparison, and it was found that the turbine ship was brought to'a stop in the water in slightly less time than that occupied by the engine driven ship. I am informed that during the trials the turbines gave no trouble and their practical operation was entirely satisfactory. -- Each turbine is built in the form of a drum shaped shell built in sections the shell having a length of about 11% ft. and an outside diameter of a little over 8% ft, the reversing apparatus. being all contained within the same shell. 'The weight allowed for each turbine was - tons and the actual weight was 57 tons. A very remarkable feature of the result seems to be the screw performance at the unusually high revolutions. Three or four pairs of screws were tried before the desired result was obtained, the turbines originally having been intended to run at 600 revolutions. The characteristics of the screw we have not as yet ascertained and cannot, there- fore, state them, but it would seem from the excellent performance of the propelling machinery as a whole that the screws must have been surprisingly efficient in their action, considering the fineness of pitch involved. Shop tests of the turbine to ascertain their H. P. econo- my had previously been conducted, the power developed being measured by a disc water brake with the following results: a | With a boiler pressure of twelve atmospheres or 190 pounds abs. with dry steam and a vacuum of 28 inches the steam consumption per brake H. P. was 12.76 pounds at 600 revolutions, and about 13.42 pounds at 500 revolutions. The application of this type of turbine for driving elec- _ tric generators has received an extensive development by the General Electric Company under the very able and energetic direction of Mr. W. L. R. Emmet, who early | foresaw its advantages and who has introduced many new mecWanical features in design and construction. One novel feature introduced by Mr. Emmet was the vertical shaft form. In this form the entire weight of the rotating parts, comprising the turbine wheels and the revolving, field or 'rotor of the generator, and amounting in the larger sizes to something like 75 or 100 tons, is mounted on an oil or water step bearing, which really is not a bearing at all, but a fluid cushion support under pressure sufficient to carry the entire weight, without permitting metallic con- tact. The success of this bearing in the face of the criti- cisms and predictions often made, has been quite remark- able. The total number of turbine units thus far shipped by the General Electric Company is about 290 and those on order about 200 more. These units vary in capacity from 15 k. w. to 8,000 k. w., more than 60 percent of them ranging from 500 to 8,000 k. w. DISCUSSION ON MR. CURTIS' PAPER. Mr. Curtis: I might add that the total horse power capacity that have been delivered or are under order is some- where between 600,000 or 900,000 horse power. Mr. F. Merriam Wheeler: I wish to ask Mr. Curtis what