Verbesserte Befestigung für die Schaufel einer Gasturbine auf einer Turbinenlaufradscheibe

摘要

In a gas turbine firtree root tooth (22) structure in which a firtree root (21) is retained in a shaped slot in a turbine rotor disc (15) by means of teeth (22) cooperating with notches (26) in the slot, the bearing surface (28) of a root tooth (22) is barrelled against a planar surface (27) of the respective notch (26) so as to give point contact (29) against that surface, whereby, under load, the barrelled surface (28) crushes so as to override pitch tolerances and even out load distribution. If the barrelling is located at or in the vicinity of the tooth face centre, the tendency of the tooth to crack under repeated loadings is minimized.