Dual gas-lubricated seals use a pressurized, nitrogen gas barrier – usually at a higher pressure than the pumped fluid – combined with lift features to separate the seal faces to a small, controlled gap. Lift features – such as spiral grooves, waves, T-slots and hydropad grooves – create aerodynamic lift with the barrier gas pressure and shaft rotation, which generate a high film stiffness. This film keeps the seal faces separated, even during challenging conditions, such as vibration and cavitation.
This combination of features and design elements provides advantages not offered by other solutions. “Sealing Sense” articles in Pumps & Systems, November and December 2009, presented an overview of the basic principles of design and application of these seals.
Click here to read a “Sealing Sense” article that discusses the advantages that these unique seal designs offer when compared to other sealing solutions.