The Cla-Val Model 50-49 Pump Start Pressure Relief Valve provides pump and pipeline protection during pump start sequence and pump operation when discharge pressure rises to unsafe levels. 

Should the discharge pump pressure continue to rise due to little or no system demand, the normally closed pilot provides overpressure protection by relieving excess pressure to the atmosphere as long as the relief valve inlet pressure is greater than the pilot pressure setting. This pilot has various adjustable spring ranges to meet the system pressure requirements.