Your dust collector can be sized correctly. Your fan can be powerful enough. Your ductwork can be designed properly. But if the hood isn't capturing dust at the source, the whole system has to work harder. Effective dust collection starts where the dust starts. Learn how hood design, capture velocity, CFM, static pressure, and transport velocity work together to keep contaminants out of your facility's air.
Flap Exhaust Valves (Flap Stacks)
A resourceful after-the-fan product, flap exhaust valves, or stacks, are designed to open, like bird wings, with the airflow and close when the system is not exhausting. The lightweight and balanced blades produce minimal resistance to exhaust. The design of the housing and blades channel rainwater away from the opening and allow it to drain without intrusion into the ducting.
- Available in 4" to 32" diameter (contact for custom sizes).
- Also known as a winged stack.
- Diameters are +/- 1/8 inch.
- Alternative Solutions: No-Loss Stack, Jet Cap, Rain Cap
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