The record-union., 1897-05-19
LIKE A ROCKET.
The English Torpedo Boat "Turbinia'
Holds the Record.


The steam turbine is rapidly becom-
ing an important factor in the power
world, because of its compactness, light
weight and high speed. Over 10000
horse power in this form of driving
machinery has been installed in Eng
land alone during the past few years.
It's latest application is to the pro-
pulsion of vessels, and in this field it
has accomplished more than it's pro-
moters claimed, having established a
worlds record for speed This, too, de-
spite unforeseen difficulties that arose
in connection with the enormous speed
of the screw propellers employed .
o0O revolutions per minute which. how
ever, have been overcome in a measure,
though not entirely The vessel which
| made this record of 32ai knots was
built in England, and is known as the
"Turbinia," so named on account of its
propelling power compound steam tur-
bines. The idea of applying steam tur-
bines to marine propulsion was con-
ceived by Hon. Charles A. Parson, the
inventor of the steam turbine that bears
his name.
The Turbinia is 100 feet in length, 8
feet beam and 441a tons displacement.
1t was originally fitted with a turbine
engine designed to develop 800 actual
! horsepower when running at a speed
Of 2,oO0 revolutions per minute and di-
rectly coupled to the propeller This
equipment was changed to three
smaller compound turbine engines of
similar design, driving three propellers.
These three engines use the steam in
series, there being a high pressure, an
intermediate and a l0W-pressure engine.
| This change, however. did not increase
! the total weight of the engines and
shafts. The boiler is Of the water-t tube
type, of 223 pounds per square inch
working pressure, having large steam
space and with a total of heating space
of 11,000 square feet and a CRATE space
of ~ square feet, a remarkably small
amount considering the displacement of
the vessel and the speed attained The
stOke-h holds are closed, and the draught
supplied by a fan coupled directly to
the engine. The light weight of the ma
chinery gave a displacement only half
that required ordinarily. and the steam
consumption was almost the smallest
on record. The diameter of the pro-
pellers is only Is inches. With lower
steam pressures it is possible to still
connect directly and drive the vessel
at lower speed. There is no difficulty
about reversing, when there are several
small engines as in this case.
The greatest difficulty was encounter
ed because of the enormous speed at
which the propeller was driven, name
| ly, 1900 revolutions per minute. Or
dinarily 400 revolutions per minute is
apt to give trouble and at the higher
speed it was found that with the single
propeller there was created a cylindrical
vacuous space in the water in which
| it revolved, the blades cutting off solid
masses of water from the fore part of
walls of the space and depositing them
in the rear. The greatest part of the
power was consumed in maintaining
this vacuum. BY changing the pitch
of the propeller blades and using three
shafts this cavitation was reduced. The
action of the propeller in water was
studied by an ingenious arrangement
of reflected light from a revolving mir
ror
The hull of the Turbinia is covered
with steel plate Of a thickness ranging
from 3-16 inch on the bottom to Lie
inch in the sides near the stern.
While this vessel is only of expert
mental size there is no doubt in the
minds of it's builders that the principle
can be applied to vessels of any size.
| The claims made for steam turbine
driving, and they appear to have been
all substantiated in this boat, are
greater speed, increased economy of
steam consumption, larger carrying
~,f h. 60
1 for navigating shallow waters, greater
stability, largely reduced vibration and
reduced size and weight of screw, pro-
| pellers and shafting. Undoubtedly an
/ important principle in marine propul-
sion has been demonstrated and estab-
| lished.