The SURE-FLAP check flap system is designed to prevent flooding and backflow caused by high downstream water levels. The SURE-FLAP can and has been installed at combined sewer overflow (CSO) locations, sanitary sewer overflow (SSO) locations, holding tank overflows and pond overflows. Overloading of sewer systems and treatment plants is avoided, and energy costs for pumping systems and wastewater treatment are reduced. The SURE-FLAP also controls odors, as it is normally in the closed position.

-Up to 20 ft (6 m) headroom

-Modular construction up to 20 ft (6 m) long

-Rigid stainless steel flap

-Hydraulically ideal shape

-Airtight design for odor control

-Low hydraulic resistance

-Easy to adapt to existing installations

-Stainless steel construction

Application scope

The SURE-FLAP check flap may vary from model GSF-40-* to GSF-100-*. The GSF-40-* is designed to fit over a concrete opening measuring 16 inches (40 cm) high and up to a maximum width of 20 feet (6 m), and the GSF-100-* is designed to fit over a concrete opening measuring 40 inches (100 cm) high and up to a maximum width of 20 feet (6 m). SURE-FLAP model selection is based solely on the size of the concrete opening. Units are currently marked with an asterisk due to the wide variety of model options.

How it works

The SURE-FLAP non-return flap is a stainless steel swing check flap mounted on a rectangular concrete opening. In its resting position, the SURE-FLAP hangs vertically under its own weight, closing and sealing the opening. If the water level in the sewer or reservoir overflow rises, hydrostatic pressure against the SURE-FLAP check valve causes it to open, allowing water to flow over the weir. If the downstream water level rises, the SURE-FLAP is pressed against the concrete opening so that no water can flow back into the sewage system, reservoir or pond. The SURE-FLAP's lightweight design makes it highly responsive to minimal changes in water level, while ensuring structural stability under conditions of high downstream water levels.

The SURE-FLAP Check Flap can be fitted with a stainless steel frame for anchoring in concrete or anchoring to the structure. This flat, smooth sealing surface will increase the flap's watertightness and avoid potential problems caused by openings and uneven concrete surfaces.