A ring, made of a pliable rubber-like material, that forms the end of the bellows which surrounds the spout of a balance system vapor-recovery nozzle. When the nozzle is inserted and the bellows compressed, the face seal makes a snug connection with the lip of the vehicle’s fill pipe. A worn seal may be removed and replaced without taking the nozzle out of service.

 

The term face seal is also used to describe a carbon seal used on the shafts of petroleum centrifugal pumps.