Critical Flaw Estimate and Flaw Analysis of 81-mm M821A1 Mortar Projectile

摘要

Recent inspection of 81-mm mortar shells indicated the presence of flaws extending up to a third of the way through the wall thickness, as well as flaws internal to the shell body. Although no injuries have been recorded, this prompted an analysis of the mortar shell to determine what the critical flaw size is. Using the ABAQUS software, the mortar shell was analyzed with and without flaws to determine if the part would survive the loading of hydro testing and gun launch. The NASGRO software package was also used to find the critical flaw size for the shell. The critical flaw size was determined to be one fourth of the way through the wall thickness of the mortar body and was recommended as an inspection criterion for acceptance of 81-mm mortar shell parts. parts.