A dual pressure relief device system that provides a safe, efficient method of switching from an active PRV to a standby, maintaining system overpressure protection
Liquid/two phase service Safety Selector Valves can be used in gas/vapor, steam, liquid or two-phase service. Figure 1 shows an Anderson Greenwood Series 400 pilot valve relieving on liquid only. Figure 2 shows the same valve transitioning to two phase flow as gas becomes entrained in the relief stream. Section I steam service As per ASME Section I Boiler and Pressure Vessel Code Case 2254, the Safety Selector Valve can be installed to provide a back-up safety valve for boilers with a maximum allowable working pressure (MAWP) of 800 psig or less. The code case requires that the switchover device must provide: positive locking, external bleed valves, certified Cv values. The SSV will provide the highest flow efficiency (Cv) of any switchover device in the same nominal pipe size, enabling it to be used with most manufacturers’ flanged Section I Boiler valves. To ensure complete compliance with the code case, please provide the model number and set pressure of the safety valves to be used.
Up to 6001.66 psig
-425°F - +801°F