162mm flanged Flush vacuum relief vent

The primary function of the flush vacuum relief valve is to prevent vacuum induced damage to the shell as a result of rapid decreases in tank pressure due to product cooling or failure to open the manhole lid during product discharge. Designed with a large surface area and high flow rate performance. The flush vacuum relief valve will open under negative pressure to protect the tank from damage that may occur under vacuum conditions. The flush vacuum relief valve can be fitted either directly to the road tanker or AMF manhole cover.