Material Rate User Manual
Great Plains Manufacturing, Inc. Table of Contents Liquid Fertilizer Rates 93
2014-03-17 Table of Contents 411-020B
Orifice Plate Selection
Skip this step if using VeriFlow nozzles.
Refer to Figure 23
Agricultural Chemical Hazard:
Wear protective gloves when changing orifice plates.
In general, the orifice needs to be small enough to
create at least 15 psi of pressure in the manifold but
large enough to prevent the manifold pressure from
exceeding 65 psi.
The minimum pressure is required to even out the flow of
fertilizer between rows. To reduce orifice plugging and
pump wear, use the largest orifice practical for your
fertilizer application rate.
The best pressure range to maintain is 15-to-40 psi to
ensure optimum distribution while minimizing leakage.
Orifice Size Does Not Control Rate:
Orifice size is only used to create 15-to-65 psi back pressure to
provide even flow between rows. Set application rate in gallons
per acre using pump drive chart.
Row Shutoff
Unused drop lines may be shut off by replacing the
nozzle with a Great Plains 832-051C cap .
Nutri-Pro
®
boom systems typically have more nozzles
than coulters, and include caps for unused rows.
When installing a cap:
• It is not necessary to remove the gasketed orifice plate
from inside the clamp. The cap includes its own gasket
that seals at the end of the clamp port.
• Use a tie wrap or other line to secure the loose nozzle
and drop line tubing to the boom.
• Adjust pump and/or orifice plates for new rate and row
spacing.
Mis-Application or Material Loss Risk:
Do not apply materials after row shut-off or row turn-on
without first reviewing setup. Merely changing the number of
active rows does not change the application rate. If pump
and/or orifice size changes are not also made, pressures could
be too low or too high.
Figure 23
Fertilizer Orifice Plate
29984
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3
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Orifice Part Port Port
Size Number Diameter Area
20 832-052C 0.020 in 0.20 mm²
28* 832-056C 0.028 in
0.40 mm²
34* 832-053C 0.034 in 0.59 mm²
48* 832-054C 0.048 in 1.17 mm²
59 832-057C 0.059 in
1.76 mm²
80 832-055C 0.080 in 3.24 mm²
98 832-059C 0.098 in 4.87 mm²
29993* Sizes standard in many fertilizer bundles.
Check your accessories before ordering.
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