Non destructive testing of spacecraft propulsion system tankages

The spacecraft propulsion system tankages are of fracture controlled design. Non destructive testing (NDT) and control methodologies in the form of intermediate checks, standard inspection and specialised inspection ensure that the tankages are free from unacceptable defects. Of the many a NDT techniques employed, x-ray radiography is used in both standard inspection and specailised inspection. Defect characterisation by radiographic technique include modified triangulation technique for location of defects and estimation of the depth of defect. Another application of x-rays as an alignment tool during blind electron beam welding (EBW) is also discussed.