The Republican., 1946-07-11
BARN HAY FINISHER

The barn hay drier or finisher was
developed in this country by the Uni
| Iversity of Tennessee and the IVA
with various notifications, it has
| Espread throughout good part of the
Eastern and Central states. About a
dozen such units are now being used
| in Maryland. Their big advantage
when well made, is top quality hay
with all the leaves and the feed val
| Tue saved. It's one way farmers have
of growing more and better feed at
home and buying less grain. Where
lever rains come in haying season,
barn dricrs show promise.
A typical barn drier consists Of a
fan or blower installed near the mid
die of one end of the barn. The fan
Imay be i'm small room built in the
barn or it may be bOlted to the barn
wall, depending on the type Of fan
used and ON the barn itself. This fan
blows air into large main duct
which is built on the NOW floor and
reaches to near the other end of the
barn. About every four feet along
both sides of the main duct small
branch duct is built to carry the air
out toward the sides of the barn. The
branch ducts are provided with holes
or slots along both sides to let the
air into the hay uniformly, Partial
ly dried hay is placed over this
duct system, much as completely
cured hay is placed in a NOW. Some
care is needed to get uniform cover
ing so not all the air will pass
through a few loose spots while some
tight spots are not dried at all. Not
more than eight feet of damp hay
should be placed over the system at
one time.
Success of such a drying system is
dependent about equally on proper
duct design and fan selection and ON
judicious operation. A poorly de-
signed system will not operate salts
factorily even with the best of care.
Nor will good system make quail
ity hay from poorly placed forage
which is not dry enough when
brought into the barn.
Large ducts with low air vclocities
eliminate the need for refinements
such as splitters, scoops and similar
devices which are used to reduce
losses in a high velocity duct system
In tapered main duct, air velocities
should not exceed 1900 linear feet per
minute In a main duet of uniform
cross section, 1000 feet per minute is
the maximum for uniform results
Branch duct velocities should not be
over 1900 feet per minute. The in
side of all ducts should be smooth and
free from braces or obstluctions.
Fan selection requires the utmost
caution. Many fans and blowers have
characteristics unsuitable for hay
drier work. All hay dricr fans should
have power curves as flat as possible
so that motor can be used which
will not be overloaded under any
operating conditions. Fan speed is
important as it greatly affects cf-
ficiency. The small high speed fan
will be cheaper but will require IA
larger motor, heavier wiring and
higher operating cost. Often the
large fan installation will be cheaper
when motor, drive and wiring are
considered all together.
Two types of fans are used-cen-
trifugal blowers in which the air
moves in straight line parallel to
the shaft
Centrifugal fans should be of the
backward curved, non-overload type
as all others tend to overload the
motors when little or no hay is on
the system and fail to deliver the re-
quired air when heavily loaded Back
ward curved centrifugal fans are the
most efficient for hay drier work.
Unfortunately, centrifugal fans are
expensive, heavy and bulky.
Some aXial flow or propeller fans
are satisfactory for hay drier work,
Delivery charts and tables should be
studied carefully to determine which