The Anderson Greenwood Safety Selector Valve allows for continuous overpressure protection while never exceeding the recommended 3% non-recoverable pressure losses.
The compact body design minimizes field installation costs and space requirements and can be provided tested and pre-assembled from the factory. Field-proven and industry-leading design with tens of thousands of installations worldwide in critical applications.
The Anderson Greenwood™ Safety Selector Valve (SSV) is engineered to mount two relief valves on a single vessel penetration. One mounted valve is active, providing overpressure protection, while the other acts as a mounted inactive spare. The SSV facilitates the changeover of process pressure and overpressure protection from the active relief valve to the spare with no process vessel downtime.
Unplanned outages in critical applications can be extremely expensive. The SSV provides an alternative for outages caused by relief valve malfunctions. Simply switch to the standby spare with no interruptions in-process and repair the failure during your next turnaround.
How it Works
The SSV is a branching process connection that splits the process into two parallel paths. One of the flow paths is blocked by the valve seat, isolating the standby spare. The rotor and seat can be unlocked, lowered, turned, raised, and locked again to change the active flow path and pressure relief valve. Bleed valves are provided in order to vent pressure from the blocked flow path and allow for safe maintenance of the relief valve mounted above.
Unparalleled Efficiency
Unlike other fabricated block and bleed options that include pipe elbows, multiple block valves, bleed ports, or multiple penetrations, the SSV is a simple drop-in solution. Designed specifically for use with pressure relief valves, the SSV aids relief valve stability by ensuring that pressure losses through the changeover valve are below 3%.
Key Safety Features
• Designed to ensure both relief valves can never be blocked simultaneously
• Bubble-tight seating ensures personnel protection during maintenance
• Bright red active relief valve indicator ensures quick identification reducing the risk of injury
• Included Anderson Greenwood™ bleed valves can be tubed away to a safe location for bleeding of dangerous fluids
• Switching mechanism can be locked to avoid tampering
