Equipment II
Nozzles
Nozzles Selection
Low Drift Nozzles
Swath Width
Nozzles• Regulate Flow (GPM)
• Atomize liquid into droplets
• Pattern
Nozzle Materials
Brass Plastic
Stainless Steel
Ceramic
Tungsten carbide
Aluminum
Floodjet
Even Flat Fan
Broadjets/BoombustersBoominators
Tapered Flat Fan
8003
80o fan 0.3 GPM@ 40 psi
0.3 GPM = ? ounces
38.4 ounces
Nozzle selectionpage 86
GPA x MPH x W
5940 GPM =
30 GPA X 5 MPH X 20”
59400.5 GPM =
Drift
Why Interest in Drift?
• Spotty Pest Control• Wasted chemicals• Off-target damage• Higher costs - $$$• Environmental impact
– Water and Air Quality
• Public more aware of pesticide concerns! (Negative)
• Spraying in more populated areas? (Suburbs)
2%8%
24%
33%
33% Equipment
Drift
Tank Mix
Wrong Field
Off Label
Source: Farmland Insurance 1996
23%
38%
26%
13%Nozzle
Applicator
Physical
Other
WHAT IS DRIFT?• Movement of ..
• spray particles • vapors off-target
• Less effective control • Possible injury to susceptible
vegetation and wildlife.
Spray Characteristics Affecting Drift• Chemical
Properties
• Formulation
• Evaporation
• Drop size
• Volume
Equipment & Application Factors Affecting Drift
- Nozzle type
– Nozzle size
– Nozzle orientation
– Nozzle pressure
– Height of release
87% reduction in drift prone droplets < 150 microns
Low Drift Nozzles
Low Drift Nozzles
• Larger droplets • At the same flow rate • Same operating pressure than standard flat-
fan (SFF) nozzles.
PRE-ORIFICE
REDUCES LIQUID VELOCITY Reduces small droplets (200 microns) by 50 to 80 percent
Drift Potential is Influenced by:
Droplet Spectrum (Range - big to small)
Comparison of Micron Sizes(approximate)
• 2000 m
• 850 m
• 420 m
• 300 m
• 150 m
• 100 m
#2 Pencil lead
paper clip
staple
toothbrush bristle
sewing thread
human hair
Driftability of Spray Driftability of Spray Droplets of Varying Sizes Droplets of Varying Sizes
10
fee
t 1
0 fe
et
Crosswind @ 3 mphCrosswind @ 3 mph
20 20
50 50
100 100
150 150
400400
8 ft 22 ft. 48 ft. 178 ft. 1065 ft. 8 ft 22 ft. 48 ft. 178 ft. 1065 ft.
\
Nozzle Drop Size ClassesNozzle Drop Size Classes
Very Fine to Fine < 200 um
Medium to Coarse – 200 to 450 um
Very Coarse > 450 um
Tip Spray Selection by Drop Size
Turbo TeeJet Flat-fan
Secondary Break-UpSecondary Break-UpDroplet elongation and fracture produces small Droplet elongation and fracture produces small
dropletsdroplets
\
Sources of Spray Mist or Fines Sources of Spray Mist or Fines Secondary Break-UpSecondary Break-Up
Droplet elongation and fracture Droplet elongation and fracture produces small droplets produces small droplets
\
Sources of Spray Mist or Fines Sources of Spray Mist or Fines Aerodynamic EffectsAerodynamic Effects
Air friction due to speed of the application Air friction due to speed of the application vehicle causes additional production of vehicle causes additional production of
small dropletssmall droplets
Sources of Spray Mist or Fines Sources of Spray Mist or Fines Aerodynamic EffectsAerodynamic Effects
Air friction due to speed of the application Air friction due to speed of the application vehicle is dependent upon the nozzle vehicle is dependent upon the nozzle
orientation angle. 90orientation angle. 90oo produces the greatest produces the greatest number of small dropletsnumber of small droplets
Movement
Hypro Ultra Low Drift
• 15 – 100 psi range
• 120o pattern
• $4.00 - $5.00
• Fits Standard fan tip caps
Spraying Systems DG TeeJet
• Removable Pre-orifice
• $4.50 - $5.00
• Spraying Systems• Flat Fan pattern• wider range of pressures 15
to 90 psi • produce fewer drift-prone
droplets compared to SFF.• Fits standard TeeJet
Nozzle caps
Turbo Tee Jet
Turbo Flood Nozzles
• Spraying Systems
• Clog resistant
• Wide angle
Conventional SSF
Turbo Tee Jet
25 psi at 30” spacings. 20” height
Turbo Drop Nozzle
• Greenleaf Technologies• Air Induction (AI)• Venturi pressure reduction
chamber• Droplets are filled with air
and expand when leaving tip
• Better coverage• $10.00
Tee Jet Air Induction
TeeJet Banding Tip $7 - $8.00
$6.00
• Operates at higher psi to work efficiently
• Needs special caps
CP Nozzle• Dial-an-orifice• Pattern similar to flood jet• Mainly used by aerial
sprayers
Temperature & humidity Air movement (direction and velocity)Air stability/inversionsTopography
Weather and Other Factors Affecting Drift
Evaporation of Droplets
Wind
High Relative HumidityLow Temperature
Low Relative HumidityHigh Temperature
Fal
l Dis
tanc
e
Evaporation and Deceleration of Various Size Droplets*
DropletDiameter(microns)
TerminalVelocity(ft/sec)
Final Dropdiameter(microns)
Time toevaporate
(sec)
Decelerationdistance
(in)
20 .04 7 0.3 <1
50 .25 17 1.8 3
100 .91 33 7 9
150 1.7 50 16 16
200 2.4 67 29 25
*Conditions assumed: 90 F, 36% R.H., 25 psi., 3.75% pesticide solution
Strategies to Reduce Drift
• Avoid adverse weather conditions
• Consider using buffer zones
• Consider using new technologies:– drift reduction nozzles– drift reduction additives– shields, electrostatics, air-assist
• Increase drop size
• Increase flow rates - higher application volumes• Use lower pressures
• Use lower spray (boom) heights
Polymer Drift Supressants produce larger droplets Polymer Drift Supressants produce larger droplets across the spectrum, but will decrease the fan angle. across the spectrum, but will decrease the fan angle. Nozzles on the Left have the polymer supressant.Nozzles on the Left have the polymer supressant.
Adjuvant Influence on Spray PatternAdjuvant Influence on Spray Pattern (Note Fan Angle)(Note Fan Angle)
LI 700LI 700 R-11R-11
Tallow Tallow AmineAmine
WaterWater
Adjuvant Influence on Spray PatternAdjuvant Influence on Spray Pattern (Note Uniformity of Pattern)(Note Uniformity of Pattern)
Source: FRI New ZealandSource: FRI New Zealand
Shielded Sprayers
Shrouded Sprayers
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