Cyclopedia of locomotive engineering, with examination questions and answers; a practical manual on the construction care and management of modern locomotives . and the quotient, which is ^s., is the uncor- jrected rate of steam consumption. This rate stands for the total consumption throughout the whole stroke jrepresented on the diagram by the distance from D toC, which measures in., but it is evident that thereis a small portion of the return stroke, that indicatedby the distance from E to C, during which the steam j THE INDICATOR 237 compressed in the clearance space should not
Cyclopedia of locomotive engineering, with examination questions and answers; a practical manual on the construction care and management of modern locomotives . and the quotient, which is ^s., is the uncor- jrected rate of steam consumption. This rate stands for the total consumption throughout the whole stroke jrepresented on the diagram by the distance from D toC, which measures in., but it is evident that thereis a small portion of the return stroke, that indicatedby the distance from E to C, during which the steam j THE INDICATOR 237 compressed in the clearance space should not becharged to the consumption rate, but should be de-ducted therefrom. In order to do this, multiply theuncorrected rate by the distance from D to E, whichis iyi in., or in., and divide the product by thedistance from D to C, 3^ in., or in. Thus, x - - lbs., which is the correctedrate and represents a saving by compression of = .96Jbs., or nearly per cent. In many cases the terminal pressure greatly exceedsthe compression, an illustration of which is given inFig. 109. It now becomes necessary to extend the. Figure 109 compression curve to L, a point equidistant from thevacuum line with the terminal at R. The consumptionline R. L. now becomes longer than the stroke lineR. M.; therefore the corrected rate will exceed theancorrected rate by just so much; as, for instance,erminal pressure = 34 lbs. The factor, as per Table6, = , and the M. E. P. of the diagram is 47bs. Then, 1, = lbs., uncorrected rate;,^ in. (distance R. L.)^3 in. (distancePL M.) = lbs., corrected rate, a loss of a littlenore than one pound, or about 4 per cent. 238 LOCOMOTIVE ENGINEERING ] There is another class of diagrams very frequentlyencountered, in which the terminal pressure is con-siderably below the compression curve, and in order tocompute the consumption rate by the above method itbecomes necessary to continue the compres
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectlocomot, bookyear1916
