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ISORIA 20/25 Butterfly valve
Butterfly valve

ISORIA 20/25

Centred-disc butterfly valve, sealed by elastomer liner, with lever or manual gearbox, pneumatic, electric or hydraulic actuator. Semi-lug body (T2), full-lug body (T4) or U-section body with flat faces (T5). Body types T2, T4 and T5 are suitable for downstream dismantling and dead-end service with counterflange. Connections to EN, ASME, JIS.
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Main Applications

  • Cooling circuits
  • Seawater desalination/reverse osmosis
  • Flue gas desulphurisation
  • Pulp and paper industry
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Technical Data

  • Nominal pressurePN 20, PN 25
  • Max. nominal sizeDN 1000
  • Max. allowed fluid temperature200 °C

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  • Spherically machined disc with rounded sealing contour
    • ensures durable and permanently tight shut-off
  • Splined or keyed connection without play between shaft and valve disc

    Technical Data

    • FunctionShut off/control flow
    • Connection typeInstallation between flanges, Flange
    • Design concept DriveWith electric actuator, With handwheel, Hydraulic, Lever, With pneumatic actuator, Without
    • Casing materialEN-GJS-400-15/A536 GRADE 60-40-18
    • Nominal pressurePN 20, PN 25
    • Max. nominal sizeDN 1000
    • Min. nominal sizeDN 32
    • Max. allowed fluid temperature200 °C
    • Min. allowed fluid temperature-10 °C
    • Valve body typeSemi-lug type, Full-lug type, flat faces, Full-lug type, raised faces, U-shaped body, flat faces

    Sectional Drawings


    TitleFormatSizeLast change
    TitleFormatSizeLast change
    ATEX (8610.81_EN)PDF0.44/19/2021
    Operating instructions - ISORIA/MAMMOUTH (8449.8_EN)PDF1.594/19/2021
    TitleFormatSizeLast change
    ISORIA 20/25 (8447.521_EN)PDF0.014/19/2021