US Patent 11371521 High temperature face seal

A turbomachine face seal includes a turbine wheel with a cylindrical shaft extending from the turbine wheel, defining an axis of rotation. The shaft may include a heat throttle, such as a piston ring and groove assembly, or a shaft weld pocket having an annular heat choke groove. Circumscribing the shaft is a casing and a seal ring having a groove with a seal element. To cool the seal element, a pressurized oil jet is directed toward the casing, and impinges against the casing. The oil jet may be angled or parallel with the axis of rotation. The casing may be configured to trap oil from the oil jet to cool the seal element.