. American engineer . racks. This is particularly noticeable in Fig. 20, but it alsoappeared in almost all of the curves for the individual sets ofwheels. This is no doubt due to the fact that for a there is sufficient coning of the wheels to compensatefor the difference in length between the outer and inner railsof the track, but that at some point between a 3-deg. and 6-deg. curve, there is not sufficient coning; therefore, the fric-tion for any degree of curvature beyond that point increases ata greater ratio. The numerical values for the several groups as obtainedfrom the curve
. American engineer . racks. This is particularly noticeable in Fig. 20, but it alsoappeared in almost all of the curves for the individual sets ofwheels. This is no doubt due to the fact that for a there is sufficient coning of the wheels to compensatefor the difference in length between the outer and inner railsof the track, but that at some point between a 3-deg. and 6-deg. curve, there is not sufficient coning; therefore, the fric-tion for any degree of curvature beyond that point increases ata greater ratio. The numerical values for the several groups as obtainedfrom the curves in Fig. 20. are given in Table 9. TABLE in Pounds Per Ton, for Each Group. Tange 1—Sets A, C, D 2—Sets B, E 7 5 3—Set H 9 7 4—Sets F, G 12 ; 5—Sets I, J ! A diagrammatic coiuparison of the five groups is shown inIig. 21. The average resistance in pounds per ton for all four Deg. 6 Deg. 12 Deg. 36,0. Tan. 3 6 Fig. 20—A Comparison of the Resistance According to Groups asShown on Table 9. tracks as given in Table 9 was determined for each group ofwheels, and these averages plotted as shown. This diagram in-dicates that the two first groups gave a comparatively low re-sistance. This is easily accounted for because the flanges andtreads of the first two groups of wheels were what would betermed as in good condition. The three remaining groups ofwheels, as is evident from the diagram and curves, producedconsiderably more friction than the first two groups, which isdue to high and sharp flanges, and to the absence of friction for the two worst groups is 112 per cent, higherthan for the two best groups. For this reason, wheels shouldhave as near perfect contours of flanges and treads as it ispracticable to make them, and it is very essential that onlywheels of like tape measurement be mounted upon the sameaxle. It is very important to notice that the hi
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectrailroa, bookyear1912
