Honolulu star-bulletin. [volume] (Honolulu [Oahu, Hawaii]) 1912-2010, 1916-10-10
Mill engineers
WARMLY DISCUSS
THEIRPROBLEMS
Continued from Page ~


records. They are usually placed so
that the massecuite runs into them
from the pans and is brought to any
point along the length of the centri-
fugal mixer with a screw eonyeyor or
by means of magma pump. In one
factory the massecuite Is run into the
crystalliZers with a flume Is inches
wide. 12 inches high and 100 feet long
on a 4 per cent grade and delivered
from crystallfzer to mixer by means
of a screw conYeyor IL inches In dia-
meter and 60 feet long. ....-
Usually the shipping sugars when
in the form of massecuites are left
in the crystallizers for a period of
from II to "a hours, but with the low
grade sugars about SO hours is re-
quired for Capitalization, depending
wholly upon the quality of the juices
being handled in the factory and the
methods Of sugar boiling employed In
the pans. 1t is customary. however,
to use crystallizers for low grade
sugars only. ..-.-=
Stirring Devices Vary ..~
1.-The speed of the stirring devices
varies from IA to revolution per
minute, steam, water or electricity be-
ing the motive power generally used.
Belt driven erystalliZers are, In the
opinion of the writer, to be preferred
to crystallizers which are driven by
means of shafts connecting the one
with the other. for the reason that If
there is any trouble with the worm
or gear Of any one crystallizer the
whole battery OF crystallizers is not
put out of commission pending re-
pairs. There are, however, a number
Of installations where the shaft drive
Is used. One factory on Oahu has as
many as eight crystallizers in row
driven by direct connection from one
to the other, which after two years
Of service is giving satisfaction.
1T is considered good practise where
new centrifugals are replacing old
ones to use 40 inch rather than 80
inch machines. In fact, one factory
on Maui is installing 48 inch machines,
and we have knowledge of go inch ma
chimes being advocated for Cuba. The
larger machines have found favor be-
cause of given cycle made up of
the period for starting, running and
stopping the quantity of sugar dried is
greater than in smaller machine.
Belt driven eentrifugals are in
the majority in Hawaii. water wheels
or water turbines being used together
with electric motors and the usual
steam engine for furnishing power.
Question Of Drive
THE subject of the water drive ma
chine VS.. the belt driven centrifugal is
still a live one for discussion, but
oRiAions seems to point to the fact
that the greatest efficiency is attained
with the belt driven machine because
of the small losses which occur be-
tween prime mover and centrifugal
spindle.
'1n the Lihue mill steam turbine
operating at 1900 revolutions per
minute at 90 pounds pressure belted
direct to the main drive shaft is used
to operate the centrifugal. This was
installed during the 1916 crop and has
proved to be very satisfactory.
TN conclusion II may be Of import
ance to call your attention TO the
necessity Of giving close attention to
the belts, friction brake shoes and
brake bands on belt driven machines.
II the friction brake shoes are adj
justed too close acceleration takes
place so quickly that belt slippage
becomes serious enough to iniure the
BELTS On the other hand, IL the
brake shoes are adjusted too loosely
too much time is lost in bringing the
machines up to speed. A good rule to
follow in the adjustment of brake
shoes is to have sufficient friction be-
tween the friction wheel and the
former to make it almost impossible
for the operator to hold the basket
from moving when the friction lever Is
applied,
Nothing new has developed in the
past year with reference to dis
chargers for centrifugals, but the need
for them is becoming of greater inn
Dortance, as The old hands on centri-
fugals are being replaced by men of
small stature
Respectfully submitted,
GEORGE F. WINTER,
Chairman, Committee on Cylinders
and Centrifugals
The account OF yesterday after
moons proceedings OF the engineers
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