Utilization of Computed Tomography in the absence of Metrology inspection for verification of Quality in Manufacturing of an Aerospace component

Abstract

Aerospace industry has several mission critical components of complex shape and size for single shot application which are manufactured to meet functional requirements and flight worthiness. An End dish of a rocket motor is one such component, whose functional performance under its operating conditions is highly critical. Further, the End dish has i) limited machining allowance due to design constraints ii) limited references or datum during machining and iii) packaging constraints for assembly and integration aspects due to functional requirements. During its production, Jigs, fixtures and metrology inspection are together employed to ensure manufacturing process under control. But uncertainty prevails in the quality of the End dish due to its complex shape and inaccessibility for measurement during inspection. All geometrical features of the End dish are not precisely measured through conventional and advanced metrological methods during production. X-ray Computed Tomography (CT), a non contact, non invasive, Non Destructive Evaluation (NDE) tool is employed on End dish to assess the internal details with dimensions. CT has helped in screening off End dishes with deviations prior to assembly and prevented a possible failure of the mission. CT has proven to be an indispensable inspection tool for production of End dish where Metrology data is unavailable.