Protection System - Typical case
A client requested an analysis and Dorot’s solution for his system – an uphill pumping system:

A 2200m long, 1400mm MS pipe, transporting the water from the pumping station to an elevated tank. The static lift is 29m, designed flow rate at full-capacity is 9000m3/h. The Installation was performed by Riegos de Levante, Sevilla, supplied by our agent REGABER Spain.Regulate flow into a gravity fed, large reservoir. 
Prevent water hammer and pump motor overload due to excessive flow. 

A transient analysis of the worst case scenario – a sudden stop of pumping at full capacity -  indicated the formation of considerable water hammers:

DOROT’s engineering department proposed a solution of 2 x 24” Surge- anticipating valves, which will limit upsurge to slightly higher than duty point.
 The customer insisted on limiting the transient pressure to max. 10bar, which matches the pipe class.
Engineering department has modified the solution to
 3 units, 250mm Surge-Anticipating valves, model
77-10-RE, to be installed in the pump station.
The valves open when the pressure drops below static pressure, on the initial down-surge generated by the pumping stoppage, waiting “opened” for the returning flow, thus expelling most of it out of the pipeline and slowly closing one valve at a time.