SUGARCANE - ROW APPLICATION l/ha and l/min calculations

SUGARCANE - ROW APPLICATION

Cane or sugarcane is planted locally in rows at 1.5 or 1.9 metre centres. When it comes to liquid fertiliser applications the rate per hectare is known. For example a product may be applied at 100 litres per treated hectare. The speed at which it is applied will vary due to the equipment and the terrain. When dealing with high fertiliser concentrates it may be better to apply the product to standing crops in a single or multiple solid stream pattern to minimise leaf-burn.

PRACTICAL EXAMPLE.

FERTX at 100 l/ha. Speed 6 km/hr. Cane row spacing 1.9 metres. Application as a single solid stream. Refer to page 45 in Catalogue 51M. We need to determine the flow rate of a nozzle-tip in litres per minute??

l/min = l/ha x speed in km/hr x swath or rather row spacing in metres ÷ 600

l/min = 100 l/ha x 6 km/hr x 1.9m ÷ 600 = 1.9 litres per minute

That was quite handy ...600 divided by 600 leaves 1.9. For an explanation of the 600 constant refer to the previous posting.

With a bit of algerbraic jiggery-pokery you can reverse the process and given the flow rate you can determine the litres per hectare:

l/ha = 600 x l/min ÷ km/hr x m 

l/ha = 600 x 1.9 ÷ 6 x 1.9 = 100 l/ha

Looking in the catalogue on page 45 you'll find a H1/4U SS 0006 or a TP0006-SS. At 2 bar or 200 kPa this tip delivers 1.93 litres per minute. Close enough for the real world!

By now you must be asking what do these tip numbers mean? The HU type refers to a spray-tip with a 1/4" thread male inlet, the SS stands for Stainless Steel and the 0006 refers to the angle and flow rate. The first 2 digits (00) refer to the angle and in this case it is zero degrees (solid steam)  and the 06 refers to the rated flow rate in United States gallons per minute at a specific pressure. A USGal is 3.7854 litres. An Imperial gal is 4.54 litres. (Customs officials helped themselves to the difference when they imported Scotch from across the pond) Neat little excise duty as the story goes. Anyway the 06 means 0.6 gal per minute or 2.27 litres per minute at 40 pounds per square inch or about 2.8 bar pressure.

BE CAREFUL! THE SPACING IN THE CATALOGUE IS 75 CM OR 0.75 METRES.

If you are not happy with these formulas refer to the postings covering calibration.

The real world.  Overall or broadcast application at 8'000 litres per hectare. Speed 7 km/hr. Swath 1.5 m. Flow rate?

chemicon@multispray.com

Tel Intl: +27 83 2890 327

Tel Natl: 083 289 0327