Stiffness analysis of curvic coupling in tightening by considering the different bolt structures

Curvic couplings are extensively used in aerospace machinery, such as helicopter, aero-engine, or other aircrafts. The aim of this paper is to reveal new insights into the behavior of bolted joint with curvic couplings according to the bolt geometry and physical parameters by an analytical model. The different cases are focused mainly on the different geometry characters of the bolt. The analytical results show that the compression stiffness of both the curvic and the ring part of the disc has some relationship with the curvic rotation. The curvic rotation angle and the curvic compression stiffness show a slight difference during the tightening regardless of the bolt structural parameters. However, the stiffness of the other disc parts present a more obvious difference in tightening because of the various bolt structural parameters.