Abstract: A seal assembly includes a seal disposed about a shaft and having an annular body with a radial sealing surface and an inner circumferential sealing surface engageable with the shaft. A housing is disposed about the shaft and has a first inner circumferential surface defining a first annular chamber about the shaft, the seal being disposed within the first annular chamber, a second inner circumferential surface spaced radially inwardly from the first inner circumferential surface and spaced from the outer surface of the shaft by a radial clearance so as to define a second annular chamber. A radial seal contact surface extends between the first and second inner circumferential surfaces and is sealingly engageable by the sealing surface of the seal to prevent flow between the two chambers, and circumferential pressure groove(s) are formed in the seal contact surface and are fluidly coupled with the first chamber.

Abstract: A seal assembly includes a seal disposed about a shaft and having an annular body with a radial sealing surface and an inner circumferential sealing surface engageable with the shaft. A housing is disposed about the shaft and has a first inner circumferential surface defining a first annular chamber about the shaft, the seal being disposed within the first annular chamber, a second inner circumferential surface spaced radially inwardly from the first inner circumferential surface and spaced from the outer surface of the shaft by a radial clearance so as to define a second annular chamber. A radial seal contact surface extends between the first and second inner circumferential surfaces and is sealingly engageable by the sealing surface of the seal to prevent flow between the two chambers, and circumferential pressure groove(s) are formed in the seal contact surface and are fluidly coupled with the first chamber.

Abstract: A circumferential shaft seal segment includes a radial outer face, a radially inner face, a first axial face extending from the radial outer face to the radial inner face and a second axial face axially spaced from the first axial face and extending from the radially outer face to the radially inner face. The seal has a bleed slot in the radially inner face extending from the first axial face toward the second axial face, and there are first and second recesses in the radially inner face in communication with the bleed slot that extend from circumferentially opposite sides of the bleed slot.

Abstract: A circumferential shaft seal segment includes a radial outer face, a radially inner face, a first axial face extending from the radial outer face to the radial inner face and a second axial face axially spaced from the first axial face and extending from the radially outer face to the radially inner face. The seal has a bleed slot in the radially inner face extending from the first axial face toward the second axial face, and there are first and second recesses in the radially inner face in communication with the bleed slot that extend from circumferentially opposite sides of the bleed slot.