Evening star., 1939-07-03
Rail Cancer Solved
After Long Search
By Two Scientists
Thermal Treatment Stops
Tiny 'Shutter Cracks
Which Broke Steel
BY HOWARD w. BLAKESLEE,
Associated Press Science Editor.


BY HOWARD w. BLAKESLEE,
Associated Press Science Editor.
URBANA, ILL.,, July 3.-Two slen-
der scientists here, whose combined
weight is less than two yards of
railroad rail, have been instrumental
in solving one of the big problems
of broken rails.
Their work was described in a
statement at the University Of Illi-
nois, on transverse fissure, the rail
cancer" which in 1887 caused re-
moval Of $1,000 rails in the United
States and Canada. They discovered
the cause of these assures. They
showed the railroad and steel COM
panies what traffic conditions make
cancer and proved way to end it.
The two are Profs. H. F. Moore,
weight 1876, and H. r. Thomas, 1875.
A stand rail weighs up to $50 pounds
a yard With them worked 18 engi-
neers and assistants
Study Started in 1928.
The study of rail cancer" started
here in 1928 Since then railroads
and steel manufacturers have given
more than a quarter of a million
dollars for study of this and other
rail problems.
The magnitude of rail cancer"
was shown by the Sperry car, which
detects rails about to break, al
though their exteriors are often per-
feet. This car found 1000 of the
$4,000 bad rails of 1887. But 1000
other breaks occurred in service.
Moreover, in some States the law
requires replacement of the entire
heat when three or more rails
in the lot break from cancer" This
means new rails for half a mile of
track.
The clue to the cause of Cancer"
was found in the interior of the
heads of occasional rails. There
like the interior of a honeycomb
and never near the surface, were
tiny cracks so small only a micro
scope could see them. They were
named "shatter cracks"
Under some conditions the tiny
cracks, or one of them, spread into
a break completely under the surface
but large enough nearly to cut a
rail- in two. The conditions under
which this could happen were
puzzle.
bloodhound Loads,
This was solved at the University
OF Illinois by running a loaded car
wheel millions of times to and fro
over rails set up in the laboratory.
1t was discovered that only loads
OF 10000 pounds or more, long re-
peated, would cause cancer" and
this only in the rails with the
buried cracks.
All this, however. did not solve
the problem. For it was pointed
out that 40000-pound loads seemed
improbable in actual traffic. because
wheel preSsureS are not nearly that
great even under the heaviest cars,
TO get the answer, the Illinois
scientists went out on the railroad
rights OF way. At four places, on as
many railroads and in as manv
States, they spent 8 hours a dav
for more than a dozen weeks. meas
uring the impact load of every wheel
on each passing freight.
They discovered that one wheel
in about 1000, because it has a fiat
spot, or is not quite round. or be-
cause track is not uniform does hit
the 4O,O00-pound blow. Where traf-
nc is heavy, it may take five years
lor theSe 10 produce rail cancers"
Canadian Solves Problem.
knowing how the cancer" forms,
the Illinois scientists felt their prob
lem was solved when they learned
that a Canadian metallurgist had
found how to prevent formation of
the little "shatter cracks" during
rail manufacture This itself was
one OF the surprising discoveries in
rail making. 1t was done simply
by slowing down the cooling rate
during the latter half of the regular
cooling process.
Manufacturers, trying the new
method, sent the university many
specimens of rails cooled in the new
way. Not one of these rails de-
veloped cancer" under the labora-
tory pounding. They cost per cent
more to manufacture.
The evidence was so clear that
every manufacturer became equip
ped to make them and railroads
began installing them on heavy traf-
fic lines.
Six years have passed since the
first of these rails went in. In all
that time not one cancer has been
reported from any of them. Now,
some 5000 miles of the "thermally
treated rails are down in this coun-
try and Canada. 1t is estimated
that 10 years or more will be needed
to replace the bulk of present rails.