Hattiesburg daily news. (Hattiesburg, Miss.) 1907-1908, 1907-06-23

An Expert Explains the Causes Of
Some Accidents.

Some Accidents.
To the Editor of the New York Sun
Sir: / was interested in an article
headed Freaks of Bursting Boilers"
in The Sun of July 2. for the reason
that have at last found something |
in The Sun that is not SO. / am con-
WINGED that the author Of the story
SEWER got his information from a rail-
road man.
The main premise, that locomotive
or stationary boiler explosions are due
in the majority of cases ii low water,
is primarily true. However, when it
is said that putting cold water into a
boiler that is overheated will cause
rupture, due to the sudden access Of
unrelieved pressure, a very common
fallacy that should be refuted from
that cause Experimenters, at a safe
distance; have pumped cold water over
red hot crown sheet for the purpose
of finding out whether rupture would
ensue from this cause, and it did not.
Just here let me take exception to
the following paragraph in your ar
ticle:
AS a rule the cause of a boiler ex-
plosion is shortage of water. Either
Eis low or the injectors won't work.
Now, keeping track of his water is
the one thing an engineer never neg
lects. The consequences of such neg
lect are too surely disastrous. He
: may run by all the red boards on the
road, but his guage cocks are tried
every few minutes. AS for the injec-
tors not working in such an improb-
able contingency as both being out of
order simultaneously, he has many
!. resources left him. Such contin-
gency would daunt on engineer worthy
of the name. If his water runs low
and the boiler is burned or explodes
one can usually be certain that had
the engineer lived he could have ex
planned the apparent mystery. In
I. ninety-nine cases out of hundred he
q has run his water low on purpose, sc
> as not to knock the steam down by the
g injection of cold water just before the
final struggle ito get her over thu
n hill"
The way It works out is this:
locomotive firebox is a rectangula
box of steel plates set in the back en-,
u of the boiler and secured in place b,
u hundreds of bolts, called stay bolts
= on the sides, and crown bolts on tn
II top. The crown bolts. which supper
ie the top or crown sheet of the firebo,
Ill are the danger points. Normally, tn
ie water is held from four to six inche
Is above the crown sheet. When fo
CT any reason it falls below the crow
sheet the sheet if exposed to the fir
for any lengt hof time, becomes whit
d. hot and assumes the mushy consis
ne ency of wet paper. The crown stay
Gu which are screwed through the she
and have heads on. the bottom en-
have no holding power in the softens
10 metal, the steam pressure is forciI
ny the crown sheet downward, the CROW
lh- bolts pull through the sheet, and '
ne have sagged and burned crown she
nc or in extreme cases rupture.
sh 1t is well known fact that wat
under pressure will not boil at I
same temperature as water open
the atmosphere. Therefore, when
rupture occurs in the crown sheet
lic any other part of boiler the pr
sxt sure is suddenly released with gre
IN violence from the water in the boil
'". which is at much higher temperate
ia. than PIP degrees Fahrenheit, the
lnu maspheric boiling point The result
I'VE that this water flashes into stea
ms and we have so-called called exp
Gu sion.
me No amount of cold water pump
'as over that crown sheet produces Il
on result. The effect of the cold wa
yes would be decidedly injurious to I
COZ boiler, due to the violent contract
'uii caused by the sudden cooling of
Gnu sheets and to the hardening effect
'er. the metal inherent to quenching !
~ hot steel in cold water, which lie;
to brittleness and the various otl
ills to which boiler steel is heir;
pest there would be no sudden rnsh
steam that would burst the boiler.
auo H. X Trasl