Incorporate pressure regulators into your low pressure sprinkler system if your land has varying elevations for extra water and energy savings and for the prevention of over-watering, runoff, leaching and other diseases.

On average, a Nebraska farmer uses 40 gallons of diesel fuel every year to irrigate 1 acre of crops, according to experts at University of Nebraska-Lincoln Extension. Every year, farmers and those in the agriculture industry are expected to produce more for a growing population and unfortunately, they must also work with rising energy and pumping costs that make their jobs harder.

An irrigation system requires sufficient pressure to ensure sprinklers are distributing water uniformly and with a decent reach. This pressure translates into fuel consumption at the pump. In order to conserve energy – and lower an irrigation system’s demand for fuel – farmers can incorporate lower pressure sprinkler packages and pumps into their systems and add pressure regulators to control distribution uniformity and increase system efficiency.

Low pressure sprinklers usually operate at pressures between 10 and 30 psi while still maintaining good uniformity. Coupled with lower pressure pumps, irrigators can reduce their system’s horsepower requirements to obtain significant energy savings. These savings can be augmented with the use of pressure regulators throughout the system.

Even with lower pressure sprinklers, irrigators are susceptible to water and energy wastes caused by elevation changes, changes in system demand, end guns cycling on and off and changes in water supply, all of which lead to pressure fluctuations. Pressure Regulators will help control these uncontrolled fluctuations and the resulting flow variations and distribution uniformities by limiting excess inlet water pressure to a constant outlet pressure.

Systems without pressure regulators may need to irrigate longer to compensate for irregular water application, especially when irrigating areas with varying elevations. This wastes water and directly increases pumping costs and energy consumption. In addition, unregulated systems will have over-watered areas that are at risk for disease, leaching, runoff, and soil damage. Leaching and runoff increases costs for fertilizers and can lead to pollution of ground water.

Will Pressure Regulators Work For Everyone?

Pressure regulators work hand in hand with low pressure sprinklers and pumps to lower operating costs, but pressure regulators will only provide savings if there are significant variations in flow rate. Regulators should be installed when variation in sprinkler flow rates exceeds 10%. Regulating devices will not function until the mainline pressure exceeds the determined operating pressure of the regulator. The pipeline pressure must be at least 5 psi (0.34 bar) greater than the pressure rating of the regulator.

It is also important to note that when a system runs on lower pressure it becomes critical to accurately monitor and control pressure. If you are running a system with 30 psi (2.07 bar), a 6 psi (0.41 bar) variation means a 10% flow variation. This small change in flow variation could occur with an elevation change of only 20 feet.

Design Pressure Pressure Variations
0.5 psi
(0.03 bar)
1 psi
(0.07 bar)
2 psi
(0.14 bar)
3 psi
(0.21 bar)
4 psi
(0.28 bar)
6 psi
(0.41 bar)
4.2 8.3 16.7 25.0 33.3
10 psi
(0.69 bar)
2.5 5.0 10.0 15.0 20.0
15 psi
(1.03 bar)
1.7 3.3 6.7 10.0 13.3
% Flow Variation



Sources

Reducing The Cost Of Pumping Irrigation Water – http://www.ksre.ksu.edu/irrigate/OOW/P10/Melvin10.pdf

Flow Control Devices for Center Pivot Irrigation Systems -http://www.ianrpubs.unl.edu/pages/publicationD.jsp?publicationId=742#target
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Senninger pressure regulators are known for their reliable performance, strength and durability. Senninger regulators come in a wide range of pressures and flows and are designed to meet a variety of installation needs ranging from demanding mechanized sprinkler installations to more delicate nursery and greenhouse installations. All regulators are built at our facilities in Clermont, Florida using high-impact engineering grade thermoplastics and are 100% water-tested for accuracy.