Structural Analysis of the Walleye Mark 13 Container Cover.

Abstract : This detailed structural analysis of the WALLEYE MARK 13 container cover assembly included limited nondestructive thermal testing to delineate polyvinyl chloride material dimensional stability to elevated temperatures. A detailed review of existing cover assembly inspection and repair procedure was also performed. The structural analysis investigated the concentrated stress sensitivity of the cover assembly to (undersized) width/length variations. In particular, cover stress concentrations were delineated which could occur during 'latching down' procedures of the cover to the base assembly. Stress analysis of the cover assembly demonstrated a significant sensitivity of cover stress levels to cover width and length variations from its base assembly, while the thermal testing suggested a possible cause of the failure problem. The proposed maintenance, inspection and repair procedures defined in NAVAIR Technical Manual 11-70KAA-1 should significantly reduce the potential of crack reoccurrence. However, geometric irregularities associated with difficult-to-repair cracks within the aluminum extrusion could be the source of crack re-initiation under normal cradle operational conditions. Keywords: Polyvinyl chloride; Guided weapon components; Dimensional stability; Reliability; Maintainability. (edc)