This rail is a 112-pound RE section, made of open-hearth steel at the Bethlehem Steel
Company's Bethlehem Mill, in March 1969. The month is indicated by slash marks (/). This
example has three for March, the third month in the year. One additional slash mark is added
for each month, starting with one mark for January, two for February, and so on up to twelve
marks for December.
On the opposite side of the web, additional information is stamped. An example might
be as follows:
This means that the rail came from heat No. 46331 and was the second rail rolled from the
15th ingot poured. If CC appeared here, it would indicate that the controlled cooling process was
used. Similarly, CH stands for controlled cooling and end hardened. End hardening is a special
process that reduces the effect of excess wear at the joints (par. 3.29).
3.9.
LENGTH
The length of T-rail sections has increased continually since this type of rail was
introduced. For many years, the 33-foot section was standard. Now the 39-foot length, the
military standard, is most generally used in the United States. A section of 39-foot rail fits easily
into the standard 40-foot gondola for ease of transport. Longer rails require fewer track joints
per mile, and, since joints are a source of continual trouble and expense in track maintenance,
any means of reducing this nuisance is welcomed. European railroads have used rail sections as
long as 60 feet for many years in an effort to reduce joint maintenance problems. American
lines are developing continuous welded rail for the same reason. Its advantages in economy will
become obvious as you study the section covering joints. However, it does not seem probable
that military railroads will adopt this innovation in the near future, if at all.
The disadvantages of continuous welding are twofold. First, there is the problem of a
satisfactory means of welding short rail sections together to make a continuous rail. Second is
the problem of expansion and contraction because of temperature changes, the solution to which
lies in restricting rail movement by securely fastening the rails to ties embedded in ballast. This
action sets up an
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