The BLD9132 Breather Valve has separate and distinct settings for both pressure and vacuum relief. It has a flow rate that ranges from 1.5 to 4.0 scfm at 1.5 psi above the valve reseal setting, making it suitable for containers and similar applications up to 33 cubic feet in volume. Standard settings are available from 0.25 psid to 3.0 psid reseal pressure. The lower the setting, the higher the flow rate.
The BLD9132 Breather Valve is tamper-proof and requires no field maintenance. Corrosion-resistant materials are used throughout. The valve seal is made of silicone rubber. The spherical valve seat is Teflon coated for easy "break-away" action even after prolonged storage. The manual release push button is used to equalize the pressure or vacuum differentials in order to make opening the container easier. The button is recessed in the cover to protect it from damage and eliminate the possibility that an adjacent container might press the button and inadvertently cause the valve to remain open. A unique feature of the push button is a light duty spring under the cover, separating the button from the vacuum stem, which must be overcome before the button opens the valve.
The BLD9132 valve is offered in two types: “Cracking” and “Reseal”. Cracking valves are rated by cracking pressure (the pressure at which the valve has opened enough to flow 1 cubic centimeter per minute) and the flow rate at 1.5 psi above the cracking pressure. Reseal valves are rated by reseal pressure (the pressure by which the valve is guaranteed to close after it has cracked open) and the flow rate at 1.5 psi above the reseal pressure.