. American engineer and railroad journal . of maximum forces Equality of admissions Thus, as we have already remarked, experience has shown that a moderate fall of pressure in the receiver is not only without disadvantage, but actually presents a real advantage. Instead of expressing that this fall of pressure is naught, we could perhaps be led to assume that it has a determined value, c; equation (2), above evolved, can be now replaced by the following: Pf Pf = C- (2 bis) Kf 1 Let us take as before P=15 kilograms and D = , and we will make c =; J kilogra
. American engineer and railroad journal . of maximum forces Equality of admissions Thus, as we have already remarked, experience has shown that a moderate fall of pressure in the receiver is not only without disadvantage, but actually presents a real advantage. Instead of expressing that this fall of pressure is naught, we could perhaps be led to assume that it has a determined value, c; equation (2), above evolved, can be now replaced by the following: Pf Pf = C- (2 bis) Kf 1 Let us take as before P=15 kilograms and D = , and we will make c =; J kilogram (1 kilogram = lbs. per square Inch). The values formed under these conditions forthese three ratios are those indicated below: K f F Equality of work Equality of maximum forces Equality of admissions !3 Although the above figures, taken as a whole, approach verynearly the coefficients actually employed in practice, they can-not of course serve any other purpose than a simple indlca-. FIG. .-i. tiou. We believe, however, to be able to make from the abovethe following legitimate conclusion: First, that for highervalues of initial boiler pressure it is best to employ greatervalues for K; second, that the values attributed to K shouliincrease with the allowable theoretical increase of the fall ofpressure in the receiver; third, that the condition of theequality of work is that which gives the least values for K .■•fourth, and finally, that the condition of the elquality of de-grees of admissions is that which allows us to adopt for K thegreatest values. It is explained from the above why—for the four-cylinderlocomotives of the hrst and second category, in which thesteam distribution in each pair of cylinders is governed by acommon valve or by two valves mounted on one valve stem(the tandem compound)—the values for K were generallymade relatively high. It is thus that we find in the locomo-tives of the Plant System of
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectrailroadengineering
