. Railroad construction. Theory and practice . he end of it. 220. Form and dimensions of metal cross-ties. Since stabilityin the ballast is an essential quality for a tie, this must be accom-plished either by turning down the end of the tie or by ha^ingsome form of lug extending downward from one or more pointsof the tie. The ties are sometimes depressed in the center (seePlate VI, N. Y. C. & H. R. R. R. tie) to allow for a thick cover-ing of ballast on top in order to increase its stability in theballast. This form requires that the ties should be sufficientlywell tamped to prevent a tendency
. Railroad construction. Theory and practice . he end of it. 220. Form and dimensions of metal cross-ties. Since stabilityin the ballast is an essential quality for a tie, this must be accom-plished either by turning down the end of the tie or by ha^ingsome form of lug extending downward from one or more pointsof the tie. The ties are sometimes depressed in the center (seePlate VI, N. Y. C. & H. R. R. R. tie) to allow for a thick cover-ing of ballast on top in order to increase its stability in theballast. This form requires that the ties should be sufficientlywell tamped to prevent a tendency to bend out straight, thuswidening the gauge. Many designs of ties are objectionablebecause they cannot be placed in the track without disturbingadjacent ties. The failure of many metal cross-ties, otherwiseof good design, may be ascribed to too light weight. Thoseweighing much less than 100 pounds have proved too 100 to 130 pounds weight is being used satisfactorily onGerman railroads. The general outside dimensions are about. (Til jnre iiiigc 2: ^ § 221. TIES. 233 the same as for wooden ties, except as to thickness. The metalis generall}^ from Y^ to f thick. They are, of course, only madeof wrought iron or steel, cast iron being used only for ^ bowls or^^plates (see § 223). The details of construction of some of themost commonly used ties may be seen by a study of Plate VI. 221. Fastenings. The devices for fastening the rails to theties should be such that the gauge may be widened if desired oncurves, also that the gauge can be made true regardless of slightinaccuracies in the manufacture of the ties, and also that shimsmay be placed under the rail if necessary during cold weatherwhen the tie is frozen into the ballast and cannot be easilydisturbed. Some methods of fastening require that the base ofthe rail be placed against a lug which is riveted to the tie orwliich forms a part of it. This has the advantage of reducingthe number of pieces, but is apt to have o
Size: 2366px × 1056px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorwebbwalt, bookcentury1900, bookdecade1900, bookyear1903
