1.3.3 Matched Precipitation

Matched precipitation heads are selected to allow full circle, half circle and quarter circle sprinkler heads to used together to provide a uniform coverage of an irrigated area.

 

The flow rates of the nozzles are proportional to the degree of arc covered. For example, the flow rate of a quarter circle spray is equal to one-quarter that of a full circle spray. The flow rate of a half-circle spray is equal to one-half that of a full circle spray. The radius of throw must be maintained constant.

 

All matched precipitation sprinklers on a lateral can be operated by one valve and the lateral will water all areas at the same precipitation rate. Think of a square with one sprinkler in the center, quarter-circle sprinklers in the corners, and half-circle sprinklers midway along the sides, if the full circle sprinkler discharges 4 gpm, the half-circle sprinkler will be 2 gpm and the quarter-circle sprinkler will be 1 gpm. Then all sprinklers will give the same application rate. Performance charts for the Rain Bird 10 Series MPR Nozzles illustrate the concept of matched precipitation nozzles. Each part circle nozzle has a fraction of the discharge rate of the full circle so they all apply the same amount of water.

 

If all sprinklers discharged the same flow rate, then separate valves would be needed for each category of sprinkler (full-circle, half-circle and quarter-circle) so they could be operated the appropriate amount of time.

 

Performance Charts
10 Series MPR Nozzles

15° Trajectory, English
Nozzle Pressure (psi) Radius (ft.) Flow (GPM) Precip (In/h) hh Precip (In/h) hh

10F

 

15 7 1.16 2.28 2.63
20 8 1.3 1.96 2.26
25 9 1.44 1.71 1.98
30 10 1.58 1.52 1.75

10H

 

15 7 0.58 2.28 2.63
20 8 0.65 1.96 2.26
25 9 0.72 1.71 1.98
30 10 0.79 1.52 1.75

10T

 

15 7 0.39 2.28 2.63
20 8 0.43 1.96 2.26
25 9 0.48 1.71 1.98
30 10 0.53 1.52 1.75

10Q

 

15 7 0.29 2.28 2.63
20 8 0.33 1.96 2.26
25 9 0.36 1.71 1.98
30 10 0.39 1.52 1.75

 

15° Trajectory, Metric
Nozzle Pressure (Bars) Radius (m) Flow (m³/h) Flow (l/s) Precip (mm/h) hh Precip (mm/h) h

10F

 

1,0 2,1 0,26 0,07 58 67
1,5 2,4 0,29 0,08 50 58
2,0 3,0 0,35 0,10 39 45
2,1 3,1 0,36 0,10 37 43

10H

 

1,0 2,1 0,13 0,04 58 67
1,5 2,4 0,14 0,04 50 58
2,0 3,0 0,18 0,05 39 45
2,1 3,1 0,18 0,05 37 43

10T

 

1,0 2,1 0,09 0,03 58 67
1,5 2,4 0,10 0,03 50 58
2,0 3,0 0,12 0,03 39 45
2,1 3,1 0,12 0,03 37 43

10Q

 

1,0 2,1 0,06 0,02 58 67
1,5 2,4 0,07 0,02 50 58
2,0 3,0 0,09 0,03 39 45
2,1 3,1 0,09 0,03 37 43

Note: All MPR nozzles tested on 4" pop-ups.
hhhh Square spacing based on 50% diameter of throw.
hhh Triangular spacing based on 50% diameter of throw.
Note: Specify spray head body and nozzle sizes separately.
Refer to Price List for shipping unit quantities.
Note: Radius reduction over 25% of the normal throw of the nozzle is not recommended.

SOURCE: Rain Bird Corporation