Spray nozzle selection
Transcript of Spray nozzle selection
Spray nozzle selection
Scott Bretthauer
Department of Agricultural and Biological Engineering
University of Illinois at Urbana-Champaign
Droplet size: influences coverage and spray drift
Small droplets provide better coverage but are more likely to drift
Need to select droplet size based on application: balance need for coverage with drift reduction
Droplet size and number
Droplet size and number
Droplet size spectrums recommended for various pesticide uses
Droplet Spectrum (by ASAE S572)
Contact insecticide
and fungicide
Systemic insecticide
and fungicide
Contact foliar
herbicide
Systemic foliar
herbicide
Soil-applied
herbicide
Incorporated soil-applied herbicide
Very fineVF
FineF √
MediumM √ √ √ √
CoarseC √ √ √ √
Very CoarseVC √ √
Extremely CoarseXC √
Calibration exampleGPA x MPH x W
5,940GPM =
GPM: nozzle flow rate in gallons per minuteGPA: gallons per acre – 15MPH: miles per hour – 7W: effective sprayed width – 20 inches5,940: constant used for converting units
15 GPA x 7 MPH x 20 inches5,940
0.35 GPM =
Calibration example
Select turbo nozzle tips
Flow rate = 0.35 GPM
Medium droplet spectrum
TT11003 @ 54 psi
Extended range flat-fan nozzleModified orificeallows operation atlower pressures
Coarse droplets
Fine droplets
Pre-orifice or drift reduction flat-fan nozzle
Pre-orifice reducespressure
Reduces small droplets
Turbo (turbulence chamber) flat-fan nozzle
Pre-orifice
Turbulence chamber
Reduces small droplets
New pre-orifice flat-fan nozzle
Pre-orifice design
One-piece fast cap
Primarily coarse and medium droplet spectrums
Air induction flat-fan nozzleInduce air into spray – increase droplet sizeMany designs – different droplet spectrums
Air induction flat-fan nozzle
Turbo air induction flat-fan nozzleCombine turbulence chambers with air induction
15 to 100 psi pressure range
Twin spray nozzles
Single tip with dual orifice design
Dual tip design
Improved penetration and coverage over single flat-fan nozzles in lower canopy of some crops
High flow rate nozzlesWide angle pattern – improved uniformityReduced formation of small spray droplets
Rate controllers and droplet sizeMonitor application factors– Flow rate– Pressure– Speed
Information entered by applicator– Effective sprayed width– Target GPA
Controller automatically maintains GPA during speed changes– Adjusts nozzle flow rate using PRESSURE– Changes droplet spectrum
Speed ChangeNozzle spacing: 20 inchesGPA: 10Initial speed: 13 MPHFlow rate: 0.44 GPMNozzle: TT11004 @ 48 psiDroplet size: Coarse
Speed ChangeIncrease speed to 18 MPHW still 20, GPA still 10Flow rate: 0.61 GPMNozzle: TT1104 @ 93 psiAbove nozzle pressure limit; unknown droplet size
Questions?Scott Bretthauer(217) 333-9418