Calibration of field crop sprayers

For you to minimise the environmental impact, by making sure your sprayer is applying precise, safe, applications in the field, demand that the sprayer is effectively calibrated. The below guide and instruction video, will explain how to make sure you get a perfect application, not just for HARDI sprayers, but also sprayers running ISO nozzles.

Calibration must always be done with clean water and before the use of any crop protection product. Follow these three steps to calibrate your sprayer:

Step 1: Check driving speed:

  • Half-fill the spray tank with water.
  • Mark out 100 m – note time to drive the distance.


If it takes 50 seconds to drive 100 metres, the spraying speed is 7.2 km/hour.


Step 2: Select volume rate, nozzle and pressure

  • For easy selection of nozzles and pressure, use the HARDI calibration disk


Step 3: Check nozzle output

  • If actual output is not equal to desired output: Readjust pressure (alternatively, change nozzle or driving speed)
  • If output has increased more than 10% from table value, change all nozzles.

Calibration formulas

When calibrating, it is the perfect time to check the spray distribution across your boom.

Here you have clean water in the whole system and a great opportunity to inspect your sprayer for any leaks, blockages, etc.


NanoDrift nozzles:

The HARDI NANODRIFT nozzles should be used when high drift reduction is required. The NANODRIFT nozzle will at low pressures reduce drift to a minimum. The droplet spectrum is coarse to very coarse; safe for drift control but without risking poor coverage and deposition on leaves.