Macon beacon. [volume] (Macon, Miss.) 1859-1995, 1871-12-23
Why steam Boilers Explode.

We copy rs follows from the New
1 York 9ritqHc Of the 23l:
4 large party Of scientific meu WeAt
/ 10 Sandy Heck, By Fpccial invitRtiOR,
yestl rday TO witness the continuation
Of the experiments begun by The vi
/ ted Railroad Companies Of New JeT-
'sey, OF the AuCgeaii0n and under lhS
immediate direction Of +. Is. SteveBA
Of HebOke1, 20 determine the cause sf
steam boiler explotlous. Among the
New York engineers present were
Den. Belknap, Chief OF the t. Il.
Board OF Supervising Inspectors Of
steamUOats; Erastus w. Smith; Nor
man WIard, Professor Thurston Of the
Stevens Institute Of Technology, and
| Charles Has1ell. A committee Ofths
Franklin Institute, OF Philadelphia,
headed by Coleman Sellers, Mr.. Collin,
Mechanical Engineer of the Pennsyl-
vania Railroad, from Altoona, and
Others, to tho number of ~ or more,
were present.
Ths first experiments Of this -eries
were made at TIOboken on the md of
Reptember last Ivy bursting four large
bollers By hydroststic pressure, and
II r. the intention oi Mr.. Htevens now
to continue them daily until the sub.
Iect Is exhausted. A large inclusurs
on the Government reservation al
Sandy Hook including about an acre
OF ground has been erected by permis-
sion Of the Secretary OF War, and
within it eight boilers have been set up
with sll the necessary appliances at
tached, four Of them being Of the lar
gcst classes of marile bOilers. After
all present had observed the details of
the preparations and examined the re-
cord Of the previous experiments, the
fire wasincreased inb1iler No. >, built
1859, and taken cut Of the tOtt in July
last, after being il use thirteen Year,.
This boiler was indentical in shape
and general construction with the
boiler which exploded on the Vest
field, although somewhat smaller,
the shell being g. feet in diameter
and - feet in length. 1t was tested
to s. pounds water pressure without
fracture on the previous occasion, and
later had been subjected to go pounds
steam pressure. Yesterday the steam
pressure was raised gradually to 81
pounds. The boiler began to leak
steam slightly at q PRESSURE Of -
pounds, and the leaking increased as
the presslre rose, till at the highest
point attained the pressure began to
recede, the leaks having increased in
the extent until the steam escaped as
fast as generated. After waiting half
an hour for the fire to burn out partl-
ally, the doors were opened and the
fires banked. At tie end of the sec.
ond half hour the tireq were with
drawn altogether, the steam pressure
having gone dow to - pounds. Soon
after the fires were drawn All exten-
sive leak started in one OF the fur
naces, probably from the sudden cool
lug aud contraction, and upon exam
iuation the boiler was found to he
much distorted. The wagOn.top had
sunk down about two inches, aud a
corresponding swell was observed in
each side, just below the depression,
All the longitudinal seams Of the
shell we're also leaking, while No
leaks were to he seen along the trans
verse seams. The experts present
seem 10 think it remarkable that an
old rotton boiler Ofsuch large dmen-
sions should be able to withstand such
All extraordinary force Of steam, and
ofcourse no satisfactory explanation
could lie drawn from this experiment,
"A to why other boilers Of like demen-
tiops, aud seemingly much greater
strength, should explode, even while
new, not only with a lower pressure
of steam than this one withstOod, hut
also with pressure much lower than
that 10 which they had been subjected
during the water test.
The second experiment was upon
No. =, hOiler made with two flat
surfaces representing the water space
between the bac6-heal and the back
connection OF the Nestfield's boiler, Ot
a part of the leg Gf ar ordinary boiler,
AMI having the same thickness Of
plate, and stsye,l with screw stays,
spaced in the same manner as in the
case OF the Wes'iicltl; the stays heiug
one and sn eighth inch in diameter,
Hith the same kinds Of screw threads,
and similar rivcting over ut the en- Is.
rhis structure was set up between two
brick furnaces, and had previously heeu
subjected to one hundred aud thirty
eight pounds Of hydrostatic pressure.
Ii began to leak slightly when the
steam pressure reached l9J pound5
anh burst tXplosively from the pull
lug ont Of the stays at 1875 pounds pres
sure. The parts we're thrown 10 Il
great distance, entirely demolishing
the brick furnaces, aud leveling them
with the ground. One of the parts
stIrck large bOil.r in which there
Was = low pressure of steam about fifty
fctt away, breaking hole in it eigh-
teen iuchcs long and four inches wide,
from which its contents escapel, fill
ing the whole inclOseure with cloud
Of steam Mr.. Stevens had wisely in
sisted upon keeping sil the spectators
3"n feet away, and no one Was injured,
: In this expt rimert it was again shown
that an extraordinary pressure i,
necessary to rupture even the weakest
parts OF boilers, as ordinarily cOnstruc.
ted-namely the tllt surface; aud i;
became fully evident that further ant
] different experiments must be tried il
e order to determine why boilers explo,l,
a. prf.,ures generally lowerthSn lhce,
to which b,th these blilerS had b,e,
D sui j~cted, or else il must be believe,
1 either that the pre>sures are muct
e greater than has been supposed or in
!, dicAted by steam-gaugts aud safety
i valves, or that some fOrce is actin!
!, upon the boilers not indicA'ed bl tn,
Z ordinary metres placed upon them.
n IInU ia Nlepn Well