Adjusting the application rate for liquid fertilizer

The liquid fertilizer metering unit 1 is connected to the liquid fertilizer tank via the supply hose 3. The liquid fertilizer flows through the hose 2 to the application point and is applied there.

A = spray rate in gal/ac (l/ha)
A_R = pure fertilizer application rate in lb/ac (kg/ha)
G_% = fertilizer content in percent
ϱ = density in lb/gal (kg/l)

Determine the application rate for the fertilizer using the equation.

D = flow rate gpm (l/min)
A = spray rate in lb/ac (kg/ha)
v = forward speed mph (km/h)
R_W = row width in ft (m)

Determine the flow rate with the equation.


Flow rate
Valve setting	Pressure
Valve setting	14,5 psi (1bar)	21,76 psi (1,5bar)	29,01 psi (2bar)	36,26 psi (2,5bar)	43,51 psi (3bar)	50,76 psi (3,5bar)	58,02 psi (4bar)	65,27 psi (4,5bar)	72,52 psi (5bar)	79,77 psi (5,5bar)	87,02 psi (6bar)	94,27 psi (6,5bar)	101,53 psi (7bar)	108,78 psi (7,5bar)	116,03 psi (8bar)
1	0,11 gpm (0,43l/min)	0,14 gpm (0,52l/min)	0,16 gpm (0,6l/min)	0,16 gpm (0,62l/min)	0,18 gpm (0,68l/min)	0,19 gpm (0,73l/min)	0,2 gpm (0,77l/min)	0,22 gpm (0,85l/min)	0,25 gpm (0,93l/min)	0,25 gpm (0,96l/min)	0,26 gpm (0,99l/min)	2,69 gpm (10,2l/min)	0,28 gpm (1,06l/min)	0,29 gpm (1,09l/min)	0,3 gpm (1,12l/min)
2	0,16 gpm (0,6l/min)	0,19 gpm (0,71l/min)	0,21 gpm (0,8l/min)	0,24 gpm (0,89l/min)	0,26 gpm (0,97l/min)	0,27 gpm (1,04l/min)	0,29 gpm (1,11l/min)	0,32 gpm (1,2l/min)	0,34 gpm (1,29l/min)	0,35 gpm (1,32l/min)	0,36 gpm (1,35l/min)	0,37 gpm (1,39l/min)	0,38 gpm (1,43l/min)	0,39 gpm (1,48l/min)	0,41 gpm (1,54l/min)
3	0,26 gpm (0,97l/min)	0,3 gpm (1,15l/min)	0,35 gpm (1,32l/min)	0,39 gpm (1,46l/min)	0,42 gpm (1,59l/min)	0,45 gpm (1,71l/min)	0,48 gpm (1,83l/min)	0,51 gpm (1,94l/min)	0,54 gpm (2,05l/min)	0,55 gpm (2,1l/min)	0,57 gpm (2,16l/min)	0,59 gpm (2,25l/min)	0,62 gpm (2,35l/min)	0,64 gpm (2,41l/min)	0,66 gpm (2,48l/min)
4	0,38 gpm (1,44l/min)	0,45 gpm (1,72l/min)	0,52 gpm (1,96l/min)	0,58 gpm (2,19l/min)	0,63 gpm (2,39l/min)	0,68 gpm (2,58l/min)	0,73 gpm (2,75l/min)	0,77 gpm (2,91l/min)	0,81 gpm (3,08l/min)	0,84 gpm (3,18l/min)	0,87 gpm (3,28l/min)	0,9 gpm (3,4l/min)	0,93 gpm (3,51l/min)	0,96 gpm (3,65l/min)	1 gpm (3,78l/min)
5	0,53 gpm (2l/min)	0,63 gpm (2,4l/min)	0,73 gpm (2,76l/min)	0,82 gpm (3,09l/min)	0,89 gpm (3,37l/min)	0,96 gpm (3,64l/min)	1,02 gpm (3,88l/min)	1,08 gpm (4,07l/min)	1,13 gpm (4,26l/min)	1,16 gpm (4,4l/min)	1,2 gpm (4,54l/min)	1,25 gpm (4,72l/min)	1,28 gpm (4,86l/min)	1,33 gpm (5,03l/min)	1,38 gpm (5,21l/min)
6	0,81 gpm (3,07l/min)	0,92 gpm (3,47l/min)	1,03 gpm (3,91l/min)	1,14 gpm (4,31l/min)	1,23 gpm (4,67l/min)	1,32 gpm (5,01l/min)	1,41 gpm (5,33l/min)	1,46 gpm (5,52l/min)	1,51 gpm (5,71l/min)	1,56 gpm (5,92l/min)	1,62 gpm (6,14l/min)	1,67 gpm (6,33l/min)	1,72 gpm (6,52l/min)	1,8 gpm (6,8l/min)	1,87 gpm (7,08l/min)
7	1,07 gpm (4,06l/min)	1,29 gpm (4,9l/min)	1,45 gpm (5,49l/min)	1,59 gpm (6,03l/min)	1,73 gpm (6,54l/min)	1,84 gpm (6,98l/min)	1,96 gpm (7,42l/min)	2,02 gpm (7,63l/min)	2,07 gpm (7,85l/min)	2,14 gpm (8,11l/min)	2,21 gpm (8,36l/min)	2,29 gpm (8,65l/min)	2,36 gpm (8,94l/min)	2,46 gpm (9,3l/min)	2,55 gpm (9,66l/min)
8	1,53 gpm (5,81l/min)	1,75 gpm (6,63l/min)	1,93 gpm (7,31l/min)	2,12 gpm (8,03l/min)	2,31 gpm (8,73l/min)	2,47 gpm (9,35l/min)	2,62 gpm (9,93l/min)	2,69 gpm (10,18l/min)	2,76 gpm (10,44l/min)	2,85 gpm (10,77l/min)	2,89 gpm (10,94l/min)	3,03 gpm (11,48l/min)	3,12 gpm (11,82l/min)	3,24 gpm (12,26l/min)	3,35 gpm (12,7l/min)

The setting is provided in the table above.

Bring the valve 1 into the desired position.
Because the flow rate depends on the applied material:
Calibrate the application rate as specified in the operating manual for the liquid fertilizer tank.

NOTE

The determined values are reference values.
Check the setting each time the application material is changed.
For application in the seed furrow, in the headlands position liquid fertilizer can drip out of the application point.