120-mm Mortar Fuze Reduced Thread Gun Launch Survivability

摘要

A finite element analysis study was completed on the forward joint of a 120-mm mortar. The purpose of the study was to determine to what degree the adapter threads could be diametrically interrupted without compromising structural integrity during gun launch. The finite element analysis modeled the mortar assembly with a dynamic pressure load. Material nonlinearities were included in the analysis. Contact surfaces in the joint were modeled as threads. The results of the analysis indicated that four circumferential slots could be cut into the joint. For the given gun launch pressure, slots amounting to about 56% of the circumference did not result in stresses exceeding the yield strength of the joint.