V520-50 2-Way Check Valve


The Series 520-50 excess flow check valves are engineered for liquid applications in the Nuclear Power industry where personnel safety is a prime consideration. An integral solenoid valve provides remote reset capability after restoration of downstream system. Absolute zero leakage to the local environment is provided by a completely welded construction throughout the pressure envelope. Extreme reliability is inherent due to rugged design, simplicity or operation and a minimum number of moving parts. Internal parts are contoured to retard buildup of contamination and sludge.


  • Valve ratings: ANSI class 150 to 2500.
  • Resistance to contamination and sludge buildup
  • ASME Section III, Class 1-3
  • Stress and seismic analysis available.
  • Radiation resistance: 2 x 108rads
  • Solenoid operated reset capability
  • Body material: Standard Stainless Steel
  • Stellite or elastomer seats
  • Position indication switches for remote status indication.
  • Line connection : Standard – Socket weld; Optional – Butt weld or tube extensions
  • Solenoid operator is contructed of Class H material or better. 120 VAC or 125 VDC. Other voltages available.


They are designed to sense and shutoff surging fluid flow caused by a downsteam line rupture. Position switches provide remote indication when the valve has closed. Compact, light weight design provides excellent resistance to seismic vibration and shock.

Category: Nuclear Check Valves