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produce surprises. The nearer hand firing can be made to approximate continuous firing the better the per- formance will be but it is a matter of discipline entirely. No one need expect results who neglects the neces- sary steps to obtain them. Draft temperatures approximating 300 degrees should be expected, with stack temperatures even lower, but if a stack temperature much in excess of the draft temperature should be found an investigation should be un- dertaken without delay. The examples of application of cor- rective methods to existing ships fol- low. Each represents an actual ship in regular service. For more con- venient comparison the results in each case have been reduced to chart form and are shown in Fig. 2. The fuel consumptions are based on a full season’s work in each case as compared with the average of at least two, and in some instances three, previous seasons and for equal trips and approximately equal mileage and consequently include all lay time and port work. Where speeds are referred to it is to be noted that they do not mean occasional observations but are season averages of total miles run divided by total hours under way and include all slows from all causes. This is an impressive demonstration of the effect of uniform pressures, arising out of better steaming con- ditions, upon speeds, as already re- ferred to. For convenience all orig- inal performances are reduced to a common base and given a rating of 100, which indicates fuel consumption prior to alterations. The black and shaded pcrtions indicate the _ ex- tent of improved fuel performance; the solid black representing the final stage after alterations were com- pleted. See Fig. 2, page 33. Ship AA. Operating on a_ fixed route with constant mileage. Triple engine, three scotch boilers, natural draft. All auxiliaries independent, steam driven. Free steamer. Air pump single, double acting; all other pumps duplex. All in good order. Air pump, feed pumps, bilge pump, cold water pump and sanitary pump replaced by attached pumps. No other alterations of any sort. Fuel reduction as shown. Following year one boiler removed and_ positive heated draft applied to two remain- ing boilers. No other alterations. Further reduction as shown. Fuel from car weights direct from car to ship. Ship BB. Sister to AA, in same service. Same treatment as to aux- iliaries. Following year old boilers removed and two new substituted with heated draft. Results as shown. In both the foregoing instances be- fore undertaking any alterations care- ful observations were made of en- gines as to power, revolutions, points of cut-off, trim of ship, weather con- 34 ditions, etc. After alterations ob- servations were repeated under the same conditions. No difference could be detected in AA as to either power or revolutions; BB seemed to show slightly higher power and revolutions, apparently simply due to more uni- form steam conditions. Ship CC. Between head of lakes ‘and Lake Erie. ports. Triple engines, three scotch boilers, natural draft. Fair steamer but overpowered. Aux- iliaries attached except feed pump. Reduced cylinder diameters and al- tered valve gear, attached feed pumps, altered propeller, substituted two boilers with heated draft, changed feed heating system. Combined re- sult shown. Fuel, invoice weights. Speed increase with reduced cyinders, but 14 pounds increase in steam pressure 0.2 mile per hour. Dead- weight increased about 60 tons. Cost extinguished in two years. Ship DD. Between head of Lakes and Lake Erie. Sister of CC except all auxiliaries attached. Same treat- ment as CC. Combined result shown. Fuel invoice weights. Speed increase with reduced cylinders and 10 pounds higher steam pressure, 0.35 miles per hour. Deadweight increased about 60 tons; cost extinguished in two years. Ship EE. General cargo _ trade, Triple engine, three scotch boilers, natural draft. Removed one _ boiler and fitted heated draft to remaining boilers. No other alterations. Re- sult shows average of year’s work- ing as compared with previous years. Increased deadweight about 70 tons. Fuel, invoice weights. Cost extin- extinguished in one season. Ship FF. Operating on nearly con- stant route and mileage. Triple en- gines with all auxiliaries independ- ent steam driven, duplex. All in good order. Two scotch boilers with natural draft. Hard steamer. Sub- stituted attached auxiliaries. No other alterations of any kind. Results as shown. Ship steaming freely and without effort. No reduction in power or revolutions but an increase in average speed of 0.1 mile per hour at same point of cut-off as before alterations, due apparently to uni- form steaming conditions. Fuel, car weights from car direct to ship. Cost extinguished in one season. Ship GG. Package freighter. Triple engines, two scotch boilers, mechanical heated draft. All auxiliaries at- tached. Hard steamer. Remodeled draft system, increasing both air heating surface and draft area and reducing air velocities. No other alterations. Stack temperature re- duced over 250 degrees, draft tem- peratures increased over 100 degrees, air pressures reduced and stokehold conditions greatly improved. Smok- ing largely abated. Results as shown. Speed increased about 0.3 mile per hour due to better steaming. Fuel invoice weights. Cost extinguished in one season. Ship HH. Same as FF. but with at- tached auxiliaries. Very hard steam- er. Reduced grates from 7 feet to 4 feet 6 inches and added ventilation to firehold and supplied feed water heater. No other alterations of any kind. Ship steaming freely and with- out effort. Comparative results shown. Speed increased average 0.6 mile per hour due to more uniform steaming. MARINE REVIEW—May, 1927 Fuel, car weights direct from car to ship. Cost extinguished in two trips. Ships JJ, KK, LL, and MM. Sisters operating on fixed routes with con- stant mileage. Triple engines, three scotch boilers, natural draft. Fair steamers under good weather condi- tions. All auxiliaries independent duplex. All machinery in good or- der. Observations as to powers, revo- lutions, etc., before undertaking any alterations and points of cut-off marked. Attached auxiliaries substi- tuted for independent. No other al-. terations. Average result as shown. No reduction in power or revolu- tions discoverable. Following year two boilers with heated draft sub- stituted for old boilers. Average as shown. Average speed increased how- ever, 0.49 miles at same time due to improved steaming conditions and lengthened cut-off possible in conse- quence. Fuel consumption corrected for constant speed approximately as shown. Full, car weights direct from ear to ship. Cost of changing auxili- aries extinguished first season. Boiler alterations in two years. Increase in deadweight about 65 tons. Ship NN. Bulk freighter, genera] trade. Triple engines, two scotch boilers, mechanical heated draft. _Re- modeled draft system, increasing air heating surface and draft area and reducing air velocities. Increased draft temperature about 90 degrees and lowered stack temperature about 225 degrees, reduced smoking mate- rially. Result shown. Cost extin- guished in one season. The foregoing are a few examples selected out of a number as _ repre- sentative of various conditions and the possibilities of improvement with existing equipment. None of these ships represented the best thought of the builder but merely the build- er’s response to the owner’s idea of his wants, doubtless influenced more> or less by competitive conditions. If the owner prefers to subordinate the substance to the shadow doubtless that is his own affair, but the build- er should not be subjected to criticism if results are not forthcoming. There are hundreds of ships of which it is perfectly safe to say that a little study would result in large savings at small cost, and each ship is a study by herself. In many cases the cost would disappear, or be largely reduced, as maintenance and repair. As in ship HH for ex- ample in a small way, where the only actual change was in the addi- tion of a feed heater, because the fur- nace fittings required renewal in any case. The modification in ventilation was a carpenter’s job and effected in a short time with very little material. Once more the point to be driven home is that until the obvious and certain possibilities of the familiar and fairly satisfactory type of equip- ment have been exhausted it is neither good engineering nor sound business (Continued on page 48)