228 Molesworth’s pocket-book
Axles fob Railway Carhiages and Waggons.
i) = Diameter of journal in inches.
W = Weight on journal In tons.
L = Length of journal in inches.
S — Maximum stress allowed in tons per square Inch on
sectional areti of journal.
D = 2
2 VV L
3-US*
L = for carriages and waggons from 2i to 21 D.
Dimensions of Axles or Carriages and Waggons
and Tenders.
Wheel load, tons .. .. Diameter of journal, inches Length, inches 2 2i 6i 2i 2J U 3 3* 8 3i 3i 4 4i 3f 4 10 10
Minimum diameter to which journals may be turned down
<2 = 1'8 ^/w.
Load on Journal, tons W= 2 21 3 I 3i 4 4|
Minimum diameter, ins. d— 2i 2i 2f i 2J 22 a 3
Usual proportion of journal L X D per ton of load, from 8i
to 9i square inches.
Distance which axles should run without repuir, 18,000
miles. Axle tests, 3 per 100.
Vickers’ Tests for Steel Axles.
Straight axles should have an ultimate tensile strength of
not more than 23 tons per square inch. This test can only be
made by destroying the tested axles. Crank axles should
also have a-maximum tensile strength of 23 tons. The piece
of steel cut out to shape the web is the best for testing. A
piece cut off and unhannnered should bear blows until it is
bent completely double without showing any defect.