. Railway track and track work . Pennsylvania Northern Pacific * The bolt has usually an oval or square neck under the head, fitting into a holeof corresponding shape in the splice bar, in order to prevent the bolt from turningwhile the nut is being screwed on or off. Thelength of the neck should be equal to the thick-ness of the splice bar. The bolts usually havecup heads, but the heads are often too smalland too thin at the edge, so that the wear inthe edge is likely to reduce the bearing surface,especially as the contact surfaces are often toorough for a good bearing. A few roads u
. Railway track and track work . Pennsylvania Northern Pacific * The bolt has usually an oval or square neck under the head, fitting into a holeof corresponding shape in the splice bar, in order to prevent the bolt from turningwhile the nut is being screwed on or off. Thelength of the neck should be equal to the thick-ness of the splice bar. The bolts usually havecup heads, but the heads are often too smalland too thin at the edge, so that the wear inthe edge is likely to reduce the bearing surface,especially as the contact surfaces are often toorough for a good bearing. A few roads use asquare head and a grooved splice bar, both barsbeing punched alike (Fig. 42). The New YorkCentral Ry. specifies that the bolts must be ofsoft steel, f-in. test pieces showing 58,000 to65,000 lbs. ultimate tensile strength, an elasticlimit at least 50% of the tensile strength, andan elongation of at least 25% in 8 ins. The boltmust have a tensile strength of at least 50,000lbs., and an elongation of 30% or 2 ins.; itmust be bent and hammered d
Size: 1675px × 1492px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublisheretcetc, booksubject
