The Scranton tribune. [volume] (Scranton, Pa.) 1891-1910, 1899-01-02
ENORMOUS PIPE LINE.
An Australian Water Conduit over
Three Hundred Miles Long.

LhISG IluuuIeu Miles Lung
From the Engineering News.
The Coolgardie project proposes the
delivery of five million gallons of water
per day at a point in the mining re-
gions Of Australia. 32S miles from the
reservoir in the mountains near the
coast, where it is impuunded. To force
water through pipe line for this long
distance, not only must it's friction be
overcome, but it has to be actually
raised "A total vertical distance of 1870
feet. Further, the district through
which the pipe line passes is desert
whose soil is impregnated with salts,
which are said to be so corrosive to
iron that it is deemed safest not to
bury the pipe in the ground at all.
Another reason for having it exposed
Is that in a pipe line of such great
length avoidance Of leaks is essential
If an ordinary pipe line leaks Il thou
sandth part of it's flow in a mile, the
loss may be a trifling matter; vet even
50 small IA loss i'm a pipe line of this
length would amount to nearly third
Of its flow. In the arid desert through
which this pipe line will pass ii IS
thought that the soil might absorb
small leaks, so that they would not
show at all on the surface of The
ground If the pipe were buried. FaCll-
ity of inspection, therefore, is anoth n
important reason for keeping the pipe
above ground instead OF burying it,.
Besides this, the ordinary reasons fer
burying water pipes-to get them out
of the way, and to keep them from
freezing in winter--do not obtain at
ali in the region over which this pipe
line will pass: and as the cost of eX-
CaVating and back filling a trench 1913
miles long will be saved by placing the
pipe on the surface, the decision not
to bury it seems, on the whole, a wise
one.
The one great difficulty which is in
vOlved i'm keeping the pipe on the sur
face is the necessity Of providing for
expansion and contraction. In an or
dinary continuous steel conduit, the
extremes of temperature of the water
passing through it will probably not
exceed 30 degrees.
Turning now to the COOlgardie con-
dut, to be laid unprotected on the sur
face Of the ground, and with a dis
tance between pumping stations as
great as seVenty-tiVe to eighty miles,
1t is evident that the water confined
from evaporation and exposed in a
steel pipe to the fierce rays of the Aus
tralian sun may reach very high tenn
perature in its passage from one pump
ing station to the next. which i'm the
case of the longest Cunduits will re-
quire nearly three days. The English
engineers estimate the range of tenn
pcrature which will occur in the pipe
line at - degrees, and we should think
this rather an underestimate. 1t will
be seen at once that with such II range
of temperature internal strains would
be set up i'm the pipe which might be-
come so great as to cause movement
and leakage at the circumrerpntial
joints.
Expansion JOINTS are, therefore. es-
sential to the safety of the pipe, and
the English engineers propose that
such joints shall be placed at intervals
of about 12O feet for the whole length
of the conduit, which would make a
total of about 1900 expansion joints
i'm the length of the conduit.
The engineering problem presented
them (and one which We need hardly
say is without precedenO is the de-
sign of an expansion joint for pine
, Of twcnty-siX to thirty-onc inches dia-
/ meter, which shall provide for "A motion
| reaching five-eighths of an inch. which
| shall sustain presSures reaching 2OC
/ pounds per square inch, which shall be
! and remain tight, with little or no at
| tention, and which shall be as nearly
. as possible permanent part % the
! nine line