Austroads Standard 10.0:2001 section A4.3 , spray jet calibration:
The test is based on Metric nozzles, using intermediate jets Copley type AN18 and end jets Copley type EAN18, at a pressure of 95 kPa. (Formerly intermediate jets were imperial type, Copley A4 and A4N.)
Nominal nozzle spacing on the spray bar is 100mm (4 inches) with the spray bar 250mm (10 inches) above the road or ground. Nozzles are skewed at about 30 degrees to the axis of the spray bar, to prevent interference with the spray from adjacent nozzles and to give optimum spray coverage.
The following Intermediate type nozzles are available for different applications:
|
Nozzle Model Number |
Rated Flow |
Former Imperial |
GPM at 12 psi |
|
S4 |
4.5 |
S1 |
1.0 |
|
S9 |
9.0 |
S2 |
2.0 |
|
A13 |
13.5 |
A3 |
3.0 |
|
A18 |
18.1 |
A4 |
4.0 |
|
B27 |
27.2 |
B6 |
6.0 |
|
B36 |
36.3 |
B8 |
8.0 |
PRESSURE AT THE SPRAY BAR:
To give the designed rate of discharge, the pressure required at the nozzle orifice is approximately 80 kPa (0.83 Bar; 12 psi).
This pressure may be adjusted slightly to vary the discharge rate of the nozzles.
However the pressure at the nozzle orifice must never be less than 70 kPa (0.7 Bar; 10 psi). Below this pressure, the fan pattern and liquid distribution of the nozzle will not be correct.
