NASA Technical Reports Server (NTRS) 20070018135: Laboratory Reproduction and Failure Analysis of Cracked Orbiter Reaction Control System Niobium Thruster Injectors

5.8 MB·English

by  NASA Technical Reports Server (NTRS)

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ster Cracking ed thrusters found pection technique ultrasonic inspection of fleet ion to manufacturing flow ( Qual test with SN 130 & 13 33 chant and 600 F insulati manufacturing process ion immediately after bake- near new nozzle EB wel d, discovered incidentall to 1979/1982 subseque
RCS Thru ree groupings of crack 79 -SN 128, 130, 132 No Direct cause of cracking •Corrective actions •Developed ultrasonic ins •Accomplished one time •Added ultrasonic inspect •Completed 100 mission 82 -SN 322, 415, 416, 4 Cracking attributed to HF et •Corrective actions •Eliminate etchantsfrom •Added ultrasonic inspect 04 -SN 120 Counter bore cracks found First time such cracks foun Relief radius cracks similar
h 9 9 0
• • • • •
T 1 1 2
• • • •