Design Features:High Performance Butterfly Valves comply with API 609 Category B and can be used for shutoff and throttling control. They are designed to handle everything from general applications to viscous and corrosive liquids; corrosive gases and steam. A wide variety of seat types are available including the dynamic PTFE seat which provides bubble-tight shutoff in both directions; dual metal/PTFE seat for dirty, viscous services; and the Fyre Block seat, designed for fire safe applications, which meets API607 fire test standards. NACE trim, stem seal options for fugitive emissions control, pressurized neck extensions for cryogenic applications, plus many other options are available.