Abstract: A pressure balance sealing ring having a substantially S-shaped, resilient cross section including two oppositely facing convolutions, a central leg coupling the convolutions and a pair of outer legs, each extending from one of the convolutions. The ring is advantageously formed of metal and seals against opposed axially facing but offset surfaces in an annulus between two concentric pipes or opposed axially facing surfaces at the interface formed by two aligned pipes. Each outer leg has a substantially circular sealing line, these sealing lines being radially offset from one another, adjacent the free distal edge of each leg, and spaced from the convolutions. In a modified embodiment, the sealing ring has more than two convolutions and additional legs to connect them. In another series of modified embodiments, the sealing ring has one or two restraining rings rigidly coupled to one or both of the outer legs to ensure the desired direction of torsional deflection under the action of the differential pressure.

Abstract: A pressure balanced sealing ring having a substantially S-shaped, resilient cross section including two oppositely facing convolutions, a central leg coupling the convolutions and a pair of outer legs, each extending from one of the convolutions. The ring is advantageously formed of metal and seals against opposed axially facing but offset surfaces in an annulus between two concentic pipes or opposed axially facing surfaces at the interface formed by two aligned pipes. Each outer leg has a substantially circular sealing line, these sealing lines being radially offset from one another, adjacent the free distal edge of each leg, and spaced from the convolutions, In a modified embodiment, the sealing ring has more than two convolutions and additional legs to connect them. In another series of modified embodiments, the sealing ring has one or two restraining rings rigidly coupled to one or both of the outer legs to ensure the desired direction of torsional deflection under the action of the differential pressure.