drift-reducing nozzles

Drift-Reducing NozzlesRich Affeldt

Extension Crop ScientistJefferson County

Acknowledgment:Dr. Tom Wolf, Agri-Food Canada

Dr. Bob Wolf, Kansas State UniversityMark Mellbye, OSU Extension

Quick review: Nozzles Are Labeled by Spray

Angle and Output• An 8002 is?

• 800

• And?

• 0.2 gpm at 40 psi.

Choosing nozzles is usually a balance between coverage and drift potential.

Nozzle Types

Conventional Flat Fan (XR)

• Proven• Wide pressure

range• Potential for drift

Drift Reduction – Pre-Orifice

TeeJet DGDrift

GuardTurbo TeeJet

Turbo FloodJet

Drift Guard (DG)

• Pre-orifice chamber reduces internal nozzle pressure

• 30-60 psi creates similar amount of fines as normal flat fan at 15-25 psi

• Higher pressure prevents tailing-off at ends of boom Flat Fan Drift

Guard

Turbo TeeJet (TT)

• Pre orifice turbulence chamber

• Wide angle, flood-type, 15-90 psi

• Medium to coarse droplets

Turbo TeeJet (TT)

15 20 30 35 45 50 60 65 75 80 85 95 100TT 11001 C M M M M F F F F F F F FTT 110015 C C M M M M M M F F F F FTT 11002 VC C C C M M M M M M F F FTT 11003 VC C C C C M M M M M M M MTT 11004 XC VC C C C C C C M M M M MTT 11005 XC XC VC C C C C C C C C C M

Pressure (psi)

Air Induced (Venturi-type)• Venturi chamber

mixes air with spray solution

• Coarse droplets with few fines

• Not like conventional nozzles at low pressure

Air Induced (Venturi-type)

• Be aware of:– Differences in pressure operating range– Ease of cleaning– Ability to fit into existing nozzle caps

• Eight brands available in North America

TeeJet Air Induction

• Other similar designs

• Stainless steel tip• Available even fan• 40-100 psi

– Best from 60-80 psi

• Requires special cap

Greenleaf TurboDrop

• Most proven• 30-150 psi

– Best from 60-80

• TurboDrop XL– Lower pressure

version

Greenleaf AirMix

• Relatively new• Lower pressure

than most venturi-type– 15-90 psi– Best from 25-60 psi

New release in 2007:

• XR outlet with venturi air aspirator design

• More compact than AI style• 2-piece with removable pre-

orifice

AI XR TeeJet

Next Generation Air Induction Nozzles:

• More compact• Larger drops• Operates at lower pressures• Percentage of fines do not

increase with pressure

Turbo Injection - TTI

Next Generation Air Induction Nozzles:

• More consistent droplet• All-in-one cap and screen• Wide angle with 20 degree

incline• Aim forward or backword

Guardian

Volume Median Diameter

Nozzles-Recommended Use

40 psiXR nozzle

70 psi AI nozzle

Comparison with Greenleaf venturi type

% spray < 100 micron

s0

5

10

15

XR TT Venturi

40 psiAbout

2%

Comparison with Greenleaf venturi type

% spray < 100 micron

s0

5

10

15

20

XR TT Venturi

60 psi

30 psi

2%

Nozzle Summary

1. Conventional (XR) Proven, wide pressure range, drift prone

2. Pre-orifice (DG, TT) Proven, higher pressures, 50% less drift

3. Low-Pressure Air Induced (“venturi”)Reasonable press., more water, 50-70% less drift

4. High Pressure Air Induced (“venturi”)Higher press, more water, 70-95% less drift

Twin Jet Nozzles

• Often marketed for “better canopy penetration”

• Research at KSU in soybean showed less canopy penetration than a single orifice nozzle

Calibration!!!!The next phase!

Ensuring that the spray droplet spectrum is what it is supposed to be to maximize

efficacy while minimizing drift!

Volume Median Diameter

Source: Crop Life – July 2002

>150

151-250

251-350

351-450

451-550

>551

Droplet Selection/Calibration:

Droplet Spectra Classification*

Greenleaf Droplet chart:

Volume Median Diameter (VMD)

050

100150200250300350400450500

11004XR 11004TT TF 2 11003AI

Mic

rons

Water RWM + 2%AMSRWM + 1% AMS + Array RWM + 2% AMS + BorderRWM + 2% AMS + Placement

40 psi 40 psi 40 psi 70 psi

% less than 210 Microns

37 51 36 35 45 23 30 14 15 26 19 22 14 13 22 10 17 29 29 15

Bob Klein, U of Nebraska

Percent fines

On the Internet

• http://agbiopubs.sdstate.edu/articles/FS919.pdf– Summary of drift reducing nozzles

• www.bae.ksu.edu/faculty/wolf/– A leading expert on nozzle technology

• http://www.teejet.com• http://www.turbodrop.com/

– http://aandlsupply.com• Regional supplier of GreenLeaf nozzles

VariTarget:

• Speed variations from 2-20 MPH• Application rates of 5-40 GPA• Variable area pre orifice• Variable area spray orifice• Optimize spray droplet size• Maintain efficacy and minimize drift

www.spraytarget.com