Simple Screw Thread Model for Use in Finite Element Stress Analysis

摘要

A technique for modelling screw threads, such as those found on artillery projectiles, has been developed. The model employs a matrix of gap elements which are easier to use and require less computation time than the current method of modelling actual threads with material elements. Structural analysis of projectiles and other ballistic components often require the modelling of screw threads. Typically, many finite elements are required in the immediate vicinity of the joint to accurately define and model a thread. In addition, reconciling the effect of dimensional tolerances of threads is not a simple effort. For example, if an analyst were required to perform a complete analysis of a threaded region, including tolerance considerations, at least four iterations would be required. These would include the mating of large and small pitch diameter male threads (within the tolerance range) with large and small female threads (also within tolerances). (jes)