Full Product Manual

Table Of Contents
HYDRAULICS WORKSHEET
Hydrozone:
Flow (GPM):
CALCULATE: PSI
1. Static pressure at water source
Enter PSI
2. Net change in elevation from
water source to end of tubing
run
Multiply feet (+,-) by .433
3. Friction loss in mainline pipe
from water source to
hydrozone
Refer to friction loss tables in Appendix C
4. Friction loss due to fittings in
mainline pipe from water
source to valve
Usually estimate 15-20% of main line PSI
loss.
5. Friction loss due to control
zone
Refer to Table 9-5
6. Friction loss in lateral PVC pipe
from valve to top of riser in
hydrozone
Refer to friction loss tables in Appendix C
7. Friction loss due to fittings in
lateral PVC pipe from valve to
hydrozone
Usually estimate 20-25% of lateral line loss.
TOTAL PRESSURE AT INLET
Should be at least 30 PSI
Hydraulics Worksheet
Designing a low-volume irrigation system with proper hydraulics will help keep
emission devices operating properly. As a rule, you should design the system so
that at least 15 PSI of water pressure is available for flushing at the end of each
tubing run. This pressure can drop to 8.6 PSI for Landscape Dripline inline
tubing provided no supplemental emitters are used. The following worksheet
can help you organize your calculations for system hydraulics.
Page 72 Chapter 9
TABLE 9-7: RAIN BIRD PRESSURE REGULATORS
Model Size Outlet Pressure Label Color Flow Range
PSI-L30X-075 3/4" 30 PSI/2,0 BARS Red 0.1-5.0 GPM
PSI-M30X-075 3/4" 30 PSI/2,0 BARS Yellow 2.0-22.0 GPM
PSI-M40X-075 3/4" 40 PSI/2,8 BARS Yellow 2.0-22.0 GPM
PSI-M50X-075 3/4" 50 PSI/3,5 BARS Yellow 2.0-22.0 GPM
PSI-M40X-100 1" 40 PSI/2,8 BARS N/A 2.0-22.0 GPM
PSI-M50X-100 1" 50 PSI/3,5 BARS N/A 2.0-22.0 GPM
Figure 9-5: Hydraulics Worksheet
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