| 摘要 |
A breather vent mountable on the vent pipe outlet from an underground storage tank at a gasoline service station site. A vent housing includes a body section adapted for placement on the vent pipe and which cooperates with a superposed cap section to accommodate a vapor floatable valve disc supported internally thereof. Vapors from the tank can normally discharge in a primary flow path past the valve disc from where it is diverted upwardly by an annular diverging deflector to atmosphere. Displaced apertures having comparatively increased protection against freezeup form an alternative outlet for a secondary flow path diverted downwardly from a location downstream of the valve disc. The latter being better protected against freezing rain, etc. enables continued vent discharge to atmosphere in the event the primary flow path becomes ice blocked.
|
