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Roof Sump & DryDrain with Float Check Valve

Is it TRUE that a floating roof system is capable to remain completely dry? Yes, with TRUE!

TRUE is a new approach to floating roof drainage. The entire TRUE drainage system will drain into the connected off-flow system. Thus, no water will remain in the TRUE drain body.

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Roof Drain Sump TRUE Series - back view.

Key Performance Features

  • No pressure needed to close the valve with product back-flow. The rising liquid level will close the valve.

  • Full cross-section water drainage thru the drain valve body.

  • Liquid backflow will be stopped immediately. 

  • Automatic shut-off system fully resistant against hydrocarbons.

  • High-grade stainless-steel body. Zero corrosion and fully resistant to hydrocarbon and chemicals.

  • Comprehensive documented leak-test procedure prior to dispatch of each TRUE.

  • Adaptable to all existing floating roof designs.

  • Each TRUE can either be welded or bolted into the floating roof.

  • Mounting bolts also serve as stopper for larger objects to avoid clogging of the drain valve.

  • Installation options for both DIN and ANSI flanges.

  • Turnkey installation service available from our experienced and qualified field service team.

  • Short installation time.

  • Available in:

    • DN50   /   2”

    • DN80   /   3”

    • DN100   /   4”

    • DN150   /   6”

    • DN200   /   8"

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Other sizes available upon request

Roof Sump Check Valve TRUE 83
TRUE Floating Roof Sump | Dry Drain with automatic Float Check Valve | WLI GmbH

Click here to download our

TRUE Roof Sump brochure

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