East Oregonian : E.O. (Pendleton, OR) 1888-current, 1909-09-14
FINDS REASON
SMUT EXPLOSIONS
PULLMAN PROFESSOR
BLANIES MINERAL OILS
OIL Used on Thrcshcrs Becomes
Heated and Make Troublc-Vege-
table Oils VIII Not Cause Explo-
sions.

Pullman, Wash.-Professor r. w
Thatcher, director of the experiment
station and station chemist at Wash
ington state college, has been making
a study of the so-called "smut eXplo-
! sion" problem in threshing machines
and has formed the opinion that the
explosion is not due to smut, but to
the petroleum oils used by threshing
machines. Professor Thatcher said:
"By belief is that explosions are
not caused directly by smut, or. in
other words, are not explosions OF
the smut itself, but are explosions of
gases produced from lubricating oils,
by heated bearings in the machine
MY reasons for this belief are:
First-We can find no evidence or
theory for supposing that smut grains
can be changed into explosive COM
pound by heat or any other condition
which we can imagine. Second-So
far as I am able to learn there have
never been any explosions of ma
chimes where animal and vegetable
oils (Which do not give off explo-
sive gases even when heated to
high temperature) are used for lubri-
eating. Third-Lubricating oils. that
IS. those produced from petroleum
products. are known to give off ex-
plosive gases when heated to a high
enough temperature.
Railroad companies which use
large quantiti0l of lubricating oils
require that all oils shall be tested
before purchasing and shall be
brought under contract not to give
off such explosive gases below GER
tain temperature For ordinary.
black lubricating oil this temperature
is usually required 10 be not lower
than 4SO degrees Fahrenheit. while
for the best grade cylinder oils the
usual standard is about $50 degrees
Fahrenheit.
"The fact that these large purchas-
ing companies require that all sam
ples of oils submitted shall pass this
test indicates that oils are offered on
the markets which will give off eX-
ploslve gases at a lower temperature.
While we have no means of determin-
ing lust what temperature the bear
ings in a threshing machine in opera
ton may rise TO. it is quite possible
or even probable that they do often
rise to a temperature higher than that
mentioned. Moreover, the presence
of fine dust in smutty grain would ag-
grevate the tendency for the bearings
to become hot.
vegetable oils. such as castor oil
and animal oils, such as lard oil, do
NOT give off explosive gases unless
heated nearly to the temperature of
red hot iron, that is, up to 900 to
1000 degrees Fahrenheit. The wood
of a threshing machine would eaten
fire before the bearing of a machine
could reach such a temperature as
this. Hence, by the use Of vegetable
or animal oil the possibility of the
development of explosive gases would
be avoided.
"This class of lubricating oils Is
more expensive than the mineral oils
and the latter have come into gener-
al use. If my belief as to the cause
Of these explosions of threshing ma
chimes is correct then the use of lard
oil or castor oil will serve as an in
surance against such explosions
Whether this insurance is worth the
additional difference in cost between
these oils and the unsafe oils is
practical problem to be determined by
each thresher owner"