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Anderson Greenwood Series 200/400/500/700/800 Pilot Operated Relief Valves
Series 200/400/500/700/800 Pilot Operated Relief Valves
Premium performance and advanced technology for overpressure protection

Elevating Safety & Efficiency: Emerson's Revolutionary Approach to Pressure Relief Valve Monitoring

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  • Soft seat design: Provides repeatable bubble-tight performance before and after each relief cycle.
  • Metal-to-metal seat design: Provides pilot valve performance in high temperature service.
  • Bubble-tight seats near set pressure: Allows higher system operating pressure and, therefore, maximum process output; not as sensitive to vibrational and pulsating service; reduces product loss.
  • Pop action available: No main valve throttling, which helps prevent freeze-ups in cryogenic or refrigerant type services.
  • Modulating action available: Significantly cut product loss per relief situation; reduce environmental pollution; avoid oversizing consequences; not as sensitive to inlet pressure losses as pop action.
  • Field test connection: Quick, simple verification of set pressure while valve remains in service.
  • Balanced design: Lift unaffected by back pressure; no expensive and fragile bellows required to balance against high back pressure.
  • Full lift at set pressure: No overpressure required for full lift; allows D.O.T. installation to be set higher than Maximum Allowable Operating Pressure (MAOP) when pop action is used.
  • Replaceable soft seats and seals: All seats and seals are renewable easily and quickly; no expensive, time-consuming seat lapping required.
  • High Gain Modulating Action available on 400 Series pilots providing full main valve lift by 5% overpressure while significantly cutting product loss during relief events.
  • API 526 direct spring center-to-face dimensions available for Series 200, 400, 500 and 800 pilots eliminating the need for piping modifications during upgrades.