Control 3-way valve STEVI Smart - 450/451 | ARI
    Control 3-way valve STEVI Smart - 450/451 | ARI
    Control 3-way valve STEVI Smart - 450/451 | ARI
    Control 3-way valve STEVI Smart - 450/451 | ARI

    Control 3-way valve STEVI Smart - 450/451 | ARI

    The ARI-STEVI® 450 / 451 series consists of three-way control valves (mixing / diverting) designed for precise flow regulation in industrial applications. These valves are available with pneumatic (ARI-DP) or electric (ARI-PREMIO / AUMA SAR) actuators, ensuring reliable and efficient performance.

    Standard (Options)
    • DIN
    Connection (Options)
    • Flanged
    Material (Options)
    • EN-JL 1040 (GG25) Cast iron
    • EN-JS 1049
    • 1.0619+N
    • 1.4408
    Pressure Rating (Options)
    • PN 16
    Flow (Options)
    • Diverting
    • Mixing
    Actuator (Options)
    • Pneumatic
    • Electric

    Description

    Reversible pneumatic actuator with rolling diaphragm (air supply up to 6 bar)
    Electric actuators with manual override and overheat protection
    Multiple plug designs, including perforated plugs for noise reduction
    Various sealing options, including PTFE, EPDM, and stainless steel bellows
    Available in nominal pressure ratings PN16, PN25, and PN40
    Leakage class IV – VI compliance (DIN EN 60534-4)
    Explosion-proof electric actuator versions available (ATEX-compliant)



    Technical Specifications

    Valve Types & Configurations

    1. ARI-STEVI® 450 – Three-way control valve with standard sealing options
    2. ARI-STEVI® 451 – Three-way control valve with stainless steel bellows for high-temperature applications


    Material Options

    ModelNominal PressureMaterialNominal Diameter (DN)
    12.450 / 12.451PN16EN-JL1040DN15-100
    22.450 / 22.451PN16EN-JS1049DN15-150
    23.450 / 23.451PN25EN-JS1049DN15-150
    34.450 / 34.451PN251.0619+NDN15-150
    35.450 / 35.451PN401.0619+NDN15-150
    55.450 / 55.451PN401.4408DN15-150

    Other materials and custom versions available upon request.



    Stem Sealing Options

    ModelStandard SealingOptional Sealing
    450 (DN15-150)PTFE V-ring (-10°C to 220°C)EPDM (-10°C to 150°C, suitable for water & steam up to 180°C)
    451 (DN15-150)Stainless steel bellows with graphite (-60°C to 450°C)Stainless steel bellows with PTFE V-ring (-60°C to 220°C)


    Pressure & Temperature Ratings

    MaterialPN RatingTemperature RangeMax Operating Pressure
    EN-JL1040PN16-10°C to 120°C16 bar
    EN-JS1049PN25-10°C to 200°C25 bar
    1.0619+NPN40-60°C to 400°C40 bar
    1.4408PN40-60°C to 450°C40 bar


    Plug Designs & Flow Performance

    • Parabolic plug with metal seat (standard) – Leakage Class IV (DIN EN 60534-4)
    • Parabolic plug with PTFE-soft seal (max 200°C) – Leakage Class VI
    • Perforated plug (for noise reduction, metal-seated) – Ideal for gases and steam



    Actuation Options

    Pneumatic Actuator – ARI-DP 32-34

    • Max Air Supply Pressure: 6 bar
    • Spring-opening or spring-closing function
    • Handwheel for manual operation available (optional)

    Electric Actuator – ARI-PREMIO 2.2-25 kN / AUMA SAR

    • Digital actuator control with BLDC technology
    • Protection Class: IP65 (Premio), IP67 (AUMA SAR)
    • Handwheel for emergency operation
    • Integrated torque and travel switches
    • Explosion-proof models available (ATEX-certified)

    Tests and Certification

    DGRL 2014/68/EU (PED Pressure Equipment Directive)
    GOST-R (Russia)
    CRN (Canada)

    Accessories & Compatibility