A sealing assembly of an exhaust valve stem used for an engine in high temperature and high pressure

A sealing assembly of an exhaust valve stem is provided. The sealing assembly of the exhaust valve stem comprises a housing and an elastic sealing member connected with the housing. The elastic sealing member comprises a stem sealing portion used for sealing the exhaust valve stem. The stem sealing portion comprises a gas sealing lip extended radially and inwardly. The housing (32) comprises a frustum-shaped shoulder portion which is extended to a distal edge radially and inwardly in a manner facing the valve axis. The frustum-shaped shoulder portion limits the angle of a plane vertical to the valve axis, wherein the angle is between 5 and 45 degree. The distal edge of the frustum-shaped shoulder portion is disposed on the back of the gas sealing lip and is basically aligned to the gas sealing lip along the valve axis.