A second-generation spray control system that enables nozzle flow rate to be changed without altering pressure or droplet size has been introduced by TeeJet as a fitment for any standard crop sprayer.
The TeeJet DynaJet Flex 7140 controller regulates fast-acting solenoid valves that cause spray nozzles to deliver liquid in pulses of adjustable duration rather than in a continuous flow. Photo: Teejet Dynajet
The DynaJet Flex system uses fast-acting solenoids to regulate the flow of liquid through regular spray nozzles in pulses rather than a continuous flow.
Altering the duration of each "spray" pulse changes the effective flow rate; and this is used to cater for variance in sprayer ground speed to maintain a consistent application dosage.
The second-generation DynaJet Flex operates at 20Hz, twice the frequency of the first, and can handle nozzles mounted in pairs.Photo: Teejet Dynajet
Using this method rather than increasing and decreasing system pressure to alter the flow rate ensures droplet size remains consistent across a wide range of ground speeds.
But the system also allows the operator to manipulate pressure separately from the flow rate to exploit nozzles such as air induction designs that can deliver a range of droplet sizes suited to different targets and to balance optimum spray quality with the need to limit spray drift.
Watch this video showing the nozzles in action on a farm in Germany.
With the DynaJet Flex 7140 controller, the solenoid operating frequency has been doubled from 10 to 20Hz, it is compatible with section control and it can be used with installations that mount nozzles in pairs for use individually or together.
System diagnostics and solenoid fault detection are included in the controller package along with latest nozzle droplet size data.
Name: DynaJet Flex 7140
Type: Sprayer nozzle control
Key feature: Change nozzle flow rate to accommodate changes in forward speed without affecting system pressure; change spray characteristics to suit different crops and conditions
More info: Go to the manufacturer's website