Hydrodynamic face seal with grooved sealing dam for zero-leakage

摘要

A mechanical face seal includes a pair of relatively rotatable seal rings having opposing seal faces which define a sealing region therebetween. The sealing region extends radially between the inside and outside diameters of the seal rings to seal a fluid in a sealing chamber near one diameter thereof. The seal faces are provided with hydrodynamic lift features near the sealing chamber to provide a lift load that permits a liquid between the seal faces to form a fluid film therebetween. The hydrodynamic lift features primarily function to hydrodynamically generate a hydrodynamic lift load while a plurality of concentric grooves are also provided on the seal face to serve as a leakage barrier during shaft rotation of the that prevents the liquid film from leaking across the seal faces.