The Indiana State sentinel. [volume] (Indianapolis) 1868-1895, 1879-01-15
THESE EsrTNArEs

show great apparent advantage of the pro-
posed system over existing methods; and we
have no doubt of the intention TO make them
as accurate as the limited cata upon which
they are predicated will allow. The system is
on limited scale for a single season. which
can hardly be regarded sufficient TO develop
tried, the result seems 10 be PROMISING 10 ifs
projectors. and highly satisfactory to their
at Lockport evidently comprehend the re-
qunements of The system and have made very
intellig+ mt and Ingenious provisions for the
difficulties and dangers connected with it.
Whether they are such as Will per-
manently overcome these Incident 10
maintaining an extended line of steam street
mains intact in our severe climate, provide for
contraction, expansion, corrosion and
necessary decay of their costings anc
coverings, take care of the condensation, and
form their capacity for adequate supply OF
steam, WILL Of course, be fully demonstrated
Holly hss kindly furnished the following
statement OF experiments bearing directly
on these points:
TESTS REGARDING CONDENSATION.
The largest main, six inches, runs for a short
distance from the boilers, where it is reduced
TO two lines OF four inches each. We will fol.
similar lines.
Starting, then, where the four inch line
starts start d near the boiler, it passes through the
to two other lines OF three inches each. One
OF these lines runs north 200 feet TO Walnut
street, thence west !, 400 feet. making 1000 feet
in all. Here we stopped to make tests on con
densation and capacity.
RESULTS.
At the further end of the 800 feet of three
inch pipe, which was down grade ali the way,
we placed trap to separate the water from
the steam This trap was put underground,
was discharged into a tank placed on scales,
and the amount carefully weighed by an ex-
pert every half hour for twelve hours The
amount of water obtained was 81 pounds per
hour. Assuming that one pound of coal will
eyaporate nine pounds Of water, we have
VI hnT1r x af4x
per2i hours, 10 overcome condensation, with
pressure on the pipe OF Is pounds
CONDENSATION and capacity increase with
In order to show the per cent. OF loss COM
pared with the capacity OF the pipe, we made
the following test: We had a pressure of p
pounds reduced to 10 pounds Ia good warming
pressurel at the extreme end of the pipe. The
pressure was reduced by Keeping a two inch
globe valve wide open at the end of the pipe.
and small openings along the line ofthe three
inch pipe, but none within 100 feet of the
boiler. The coal was carefully weighed for
several hours, which showed that 500 pounds
Steam tn1ough the nine Then so1x9s q silo
pounds of water. Each pound OF water makes
y cubic feet of steam at the pressure of the at
mosphere; or 36)0x2S=l0J,SJ0 cubic feet OF
steam per hour. showing the per cent. of loss
by condensation to be pounds in 400, or 21s
Allowing goo cubic feet of steam per hour
for each dwelling, which will warm from H.
go TO $1,000 cubic feet OF space, according to its
Observation-Disclosures in blocks taking less
steam than those exposed on all sides-th -n
we have 100, S00-:-l ,00O=l00 dwellings, or fifty
on each side of the street, giving frontage of
40 feet TO each dwelling. Two hundred and
sixteen pounds of coal burned to overcome
condensation, divided between 100 hundred
consumers, leaves 1910 pounds per day for
each consumers share of the loss, while in
case of those who use small boilers for warm
ing separate dwellings, ii requires from 40 to 80
pounds to keep steam on such small boilers,
even without drawing or using any.
Many tests were made with regard to the
time that steam would remain in the pipes,
with The supply shut of. These tests Were
made before the service pipes were put into
any of the dwellings. Following is the result
of one: We raised the pressure to 60 pounds,
and then shut of the supply, noting the time
to condense each atmosphere. or each ID
pounds, as follows: From ~ to i5pounds it re-
quired Is minutes: from A to 80 pounds, Is
minutes: from 50 to Is pounds, 10 minutes;
from 10 pounds to the pressure of the atmos-
phere, 81 minutes; or two hours and twenty
minutes to condense the four atmospheres,
still leaving one, or l5 pounds in the pipe.
The following table will show the increase of
capacity as the pipe is enlarged, and the de
crease in condensation compared with its ca
pacity; also about the distance from the boi ler
that steam can be furnished: