PRESSURE REGULATION


This pump and filter station in Santa Rosa Valley has two sustaining valves that help keep backpressure on the filters while irrigating strawberry fields below.


The most common application for pressure sustaining valves finds them downstream of any type of self-cleaning filter. All self-cleaning filters have a minimum operating pressure requirement that can most easily be met using a properly sized pressure sustaining valve. Other common uses for sustaining valves include controlling pipeline fill-up and preventing pipeline emptying, pump overload and pump cavitation.


In low-pressure drip systems, a combination pressure reducing and sustaining control valve is often used. This is a hydraulically operated,


diaphragm-actuated control valve that sustains a minimum backpressure for a filter while reducing and never exceeding downstream pressure requirements. Just like pressure regulating valves, these valves must be sized accordingly in order to function properly.


PRESSURE RELIEF One of the most important safety features in an irrigation system is a pressure relief valve. Although there are a few types of pressure relief valves, they all function by exhausting water out of the system when pressure exceeds a desired preset value.


KNOWING WHICH FUNCTION IS NECESSARY AND WHERE TO USE IT TAKES KNOWLEDGE AND EXPERIENCE AND CAN MAKE OR BREAK A SYSTEM DESIGN.


10 Irrigation TODAY | Winter 2021


They are typically hydraulically operated and spring- or pilot-actuated control valves. If sized correctly, they respond to a system pressure spike quickly, accurately and repeatedly. When placed in the correct locations, relief valves will protect an irrigation system from accidental


Example of in-field nonadjustable regulator irrigationtoday.org


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40