BLADE RETENTION SCHEME USING A RETENTION TAB

摘要

A turbine blade retention system, for use with a rotor hub disk with peripheral circumferential array of spaced apart blade retention slots extending between the forward and rearward hub faces, each slot having a radially inward floor and side walls adapted for sliding engagement with a blade root of a turbine blade. The blade root has a bottom surface which when engaged in the slot, is radially spaced from and adjacent the slot floor thus defining a gap extending between the forward and rearward hub faces at said selected broach angle. The blade root retention tab has an elongated web with a thickness less than said gap and including a preformed transverse flange extending from a first end of the web and a second end that extends from the slot and is bent on installation into an installation flange. The web is adapted to be disposed in the gap when the web rests on the slot floor to permit sliding engagement of the blade root in the slot while the preformed flange engages one of the forward and rearward faces of the rotor hub disk. The web of the tab includes at least two deformable protrusions extending radially to a height exceeding the gap, so that the protrusions deform on sliding engagement with the blade root in the slot and secure the blade radially outward during grinding of the tip for example.