Study on collision of threaded connection during impact

For the threaded connection, elastic model and collision model were established. According to elastic deflection of thread, the axial load distribution of thread was determined and the stiffness of threaded connection was calculated. Meanwhile, collision model for threaded connection was proposed, and the calculation methods of collision time and collision force were given. Through tensile tests of threaded connections and impact experiments of projectiles penetrating into concrete targets, thread stiffness and deceleration data were obtained respectively. At the same time, finite element model were created to study the collision process on the interface of threaded connection between projectile and fuze. In order to obtain the time-frequency characteristic of deceleration, the wavelet analysis for measured deceleration and the vibration frequency analysis for projectile and fuze were conducted. The good agreement among the calculation value, finite element analysis and experiment data proved that the thread collision between projectile and fuze really exist and have very serious influence for the measured deceleration.