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Standardized Flap Gates for Round Manholes


SERIES N Flap Gates have the exact same design as the Series 60. Standardized flap gates of the most common sizes (ranging from 8in, 10in and 12in. or 200, 250 and 300mm) are kept in stock (316/316L stainless steel) and ready for delivery when needed. The NRMX configuration is made for anchoring on the face curved wall (round manhole) the extra wide flange is curved to match the inside radius of the manhole. They are very easy to install with the use of the thick wall gasket and standardized components

Serie n config nrnx


SERIES N flap gate is the simplest way to prevent flows of water from returning back into pipes or openings. The gate design is such that whatever the size, a small flow will open the gate in negative pressure but it will remain watertight for positive pressure. With its extra-wide flange and very large anchor bolt circle, the NRMX configuration is designed for installation on a curved wall (round manhole) in front of a pipe with sealant, link-seal, gasket or grout around it.

The hinges of these flap gates use a self-lubricating UHMWPE bushing to prevent metal-to-metal contact, thereby reducing friction and easing the operation. Even if the flap gate is not used for a long period of time, there is no risk that the hinges will rust or seize.

A resilient lip seal is used to achieve low leakage between the frame and flap. All SERIES N Flap Gates are made with high quality 316L grade stainless steel, ensuring the best corrosion resistance for a long life in the toughest environments with virtually no maintenance required.

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Technical documents

Serie N
Standardized Flap Gates for Round Manholes