Automatic Recirculation Valves
Automatic Recirculation Valves
The HORA Automatic Recirculation Valve PSG-N provides protection to centrifugal pumps from possible damage by thermal and hydraulic overloads at low flow rates. The automatically controlled by-pass, regulates flow to exactly correspond to that, of the pump discharge. Under zero flow conditions, the main flow path is blocked by a non-return disc/valve, influenced by a light positioning spring. The bypass would in this situation, be fully open. As demand for flow increases at the outlet of the PSG-N, the non-return valve begins to open, caused by the increase in pressure differential across the unit. At the same time, the by-pass valve begins to close. Accurate by-pass modulation control is achieved by the use of Low Noise single or multistage pressure let down components, which are designed to give protection against cavitation and flashing. Disassembly and maintenance can be facilitated with removal of the PSG-N from the line.