The strength analysis of steel sunk screw connections in the rocket

A finite element model is established to investigate the strength and slip characteristic of sunk screw connections in the rocket. A typical configuration is used as the basic model of parametric study to analyze the influence of pretension, friction coefficient and the angle of sunk head. It is found that with the rise of pretension force, the maximum von Mises of sunk screw connection decreases before the optimal pretension force and then increases, and the optimal pretension force can be predicted by finite element method. The friction coefficient has positive influence on structural behavior. With the rise of angle of sunk head, the maximum Von Mises increases and then decreases, and the position of stress concentration transfer from the middle of sunk screw to the lower edge of sunk head.