b. Horizontal split head. Horizontal breaks beginning inside the head of the rail and
spreading outward are called horizontal split heads. They are illustrated in figure 3.2D. They
are usually indicated on the side of the head either by a longitudinal seam or crack or by the flow
of metal.
c. Compound fissure. A horizontal split head which, in spreading, turns up or down in
the head of the rail is called a compound fissure. An example is shown in figure 3.2B.
d. Vertical split head. Splits may run vertically through or near the middle of the head
and extend into or through it, as shown in figure 3.2E. Such splits are called vertical split heads.
A crack or rust streak may show under the head close to the web, or pieces may be split off the
side of the head.
e. Crushed head. A flattening or crushing of the head, as shown in figure 3.2F, is called
a crushed head.
f. Split web. Cracks may run lengthwise along the side of the web and frequently
extend into or through the web. Such cracks result in what are called split webs. Figure 3.2G
shows an example.
g. Broken base. Any rail base with a crack or break in it can be said to have a broken
base. Note in the two views shown in figure 3.2H that pieces of the bases are missing.
h. Square and angular breaks. Any partial or complete break in which there is no sign of
a fissure or any of the other defects discussed, is known as a square or angular break, depending
on its shape. Examples are shown in figure 3.2I.
i. Piped rail. A vertical split, usually in the web, occurring because of the failure of the
shrinkage cavity in the ingot to unite, is called a piped rail. See the example shown in figure
3.2C.
j. Other failures. Fractures of the web at bolthole locations are dangerous and arc
discussed in more detail in section IV which treats joints and joint maintenance. Rail-end batter
is also discussed in that section as well as other failures and specific remedies.
3.11. SUMMARY
The modern T-rail is made of steel, usually refined by the open-hearth process, and
marked with its weight, section,
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