TURBOMACHINE WITH ROTATING GROUP HAVING A FASTENER ARRANGEMENT

A turbomachine 101 includes a housing 119 and a rotating group 118 that is supported for rotation about an axis within the housing 119. The rotating group 118 includes a rotor shaft 140, a wheel 130, and a fastener 232 that clamps the wheel 130 to the rotor shaft 140. The fastener 232 is unitary and includes a head 240 and a shank 242. The shank 242 includes a piloting feature 252 on an arcuate surface that faces radially outward with respect to the axis. The shank 242 is received in the wheel 130 and is attached to the rotor shaft 140 with the piloting feature 252 being piloted to an arcuate inner radial surface 178 of the wheel 130. The head 240 abuts an axial surface 251 of the wheel 130 for axially clamping the wheel 130 to the rotor shaft 140.