DAS 96-20 Evaluating forages and TMRs using the Penn State Particle Size Separator
3
GUIDELINES ON PARTICLE SIZE
(
CONTINUED
)
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Table 1. Recommended forage and TMR particle sizes for the Penn State Separator.
Corn
silage
Haylage
TMR
Upper
sieve
1
2-4%
10-15%
6-10%
(> 0.75 ")
if not sole forage
in sealed silo
or more
10-15%
15-25%
3-6%
if chopped and rolled
bunker silo, wetter mixture
focus on TNDF & FNDF
Middle
sieve
1
40-50%
30-40%
30-50%
(0.75 - 0.31")
Bottom
pan
1
40-50%
40-50%
40-60%
{<
.31")
1
Portion remaining on the screen
PARTICLE SIZE SEPARATOR INSTRUCTIONS
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The Penn State Particle Size Separator is
currently available from Nasco. For their
free phone order service dial 1-800-558-
9595. The data sheet and Weibull paper to
use with the particle size separator are
attached to the back of this publication. An
accurate scale is also needed for weighing
the samples and the boxes.
Using the separator
Stack the three plastic separator boxes
on top of each other in the following order:
sieves with the large holes (upper sieve) on
top, the smaller holes (middle sieve) in the
center and the pan on the bottom. Place
approximately 3 pints of forage or TMR in
the upper sieve.
On a flat surface, shake the sieves in one
direction 5 times. There should be no
vertical motion during shaking. This
process should be repeated 7 times for a
total of 8 sets or 40
shakes with the sieves rotated 1/4 turn after
each set of 5 shakes. See sieve shaking
pattern shown in Figure 1.
Weigh the material on the sieves and on
the bottom pan. Note that the material
above the upper sieve is greater than 0.75
inches long, the material on the middle sieve
is between 0.31 and 0.75 inches, and the
material on the bottom pan is less than 0.31
inches. See Table 2 for data entry and how
to compute percentages under each sieve.
