Airblast Sprayer Calibration

There are 3 factors to consider when calibrating your sprayer

1 - Gallons per acre to be applied (G.P.A.)
2 - Ground speed measured in miles per hour (M.P.H.)
3 - Row Spacing (Width of drive rows)

G.P.M. = G.P.A x M.P.H. x Row Space divided by 500

Example: you want to apply 50 gallons per acre to grapevines, at a speed of 3.0 M.P.H., and the distance of the drive rows is 9 foot.
50 times 3 times 9 = 1350 divided by 500 = 2.7 gallons per minute

Now look at the spray chart to determine the best way to apply 2.7 gallons per minute
You could use 10 (5 on each side) of the smallest spray tips (.8mm) at 10 bars of pressure (147 P.S.I.). Each tip produces .277 G.P.M., so 10 times .277 = 2.77

Or you might want to apply more at the top of the vine, a moderate amount at the center area, and less at the bottom. For this example we will only use 6 nozzles (3 on each side). [2] 1.2 mm tips in the top [2] 1.0 tips near the center and [2] .8 tips at the bottom. If you add up the output of these 6 tips at 15 Bar pressure (220 psi) you will get 2.73 gallons per minute.

In these examples I used a ground speed of 3 miles per hour. In reality people drive at different speeds, depending on terrain and safety factors. Use following formula to figure the actual speed you are driving. M.P.H.= (feet traveled) times 60 divided by (number of seconds it takes to travel) x 88.

(Distance Traveled in feet) x 60
(Number of Seconds) x 88

Example: Place 2 markers 100 feet apart. With a "running" start count the number of seconds it takes to travel between the 2 markers. 100 feet times 60 = 6000
If it takes 22 seconds, you multiply 22 x 88 = 1936. 6000 divided by 1936 = 3.1 M.P.H



G.P.M. Using 2 hole Stainless Steel swirl plate part number D138014

Flow Chart 0.8 1 1.2 1.5 1.8 2 2.3
5 bar (74 psi) 0.199 0.277 0.332 0.465 0.628 0.716 0.865
10 bar (147 psi) 0.277 0.396 0.501 0.699 0.819 0.956 1.093
15 bar (220 psi) 0.31 0.476 0.579 0.812 1.033 1.21 1.363
20 bar (294 psi) 0.357 0.528 0.661 1.013 1.189 1.4 1.585
25 bar (368 psi) 0.396 0.606 0.753 1.168 1.34 1.559 1.738
30 bar (441 psi) 0.462 0.687 0.802 1.263 1.414 1.717 1.839

G.P.M. Using 3 hole Stainless Steel swirl plate part number D138015

Flow Chart 0.8 1 1.2 1.5 1.8 2 2.3
5 bar (74 psi) 0.23 0.383 0.482 0.78 0.991 1.09 1.202
10 bar (147 psi) 0.284 0.482 0.606 0.946 1.223 1.357 1.515
15 bar (220 psi) 0.353 0.591 0.748 1.169 1.519 1.684 1.905
20 bar (294 psi) 0.41 0.682 0.861 1.334 1.75 1.902 2.177
25 bar (368 psi) 0.466 0.766 0.971 1.506 1.95 2.165 2.494
30 bar (441 psi) 5.11 0.839 1.049 1.625 2.147 2.361 2.787

Part Numbers for ceramic spray tips used in chart

0.8 1 1.2 1.5 1.8 2 2.3
C534039 C534047 C534043 C534044 C534060 C534045 C534061

Specifications are subject to change.