PSI - Issue 71

Sarath Chandran Nair S. et al. / Procedia Structural Integrity 71 (2025) 340–347

347

severe deformation are observed. Accordingly, all the pipes have successfully undergone flight acceptance testing and have been cleared for inducting into the cryogenic stage for human space mission. 8. Conclusions Literature survey done on polyimide pipe material and its importance in cryogenic application. Highlighted the properties of polyimide material, which are advantageous for cryogenic applications. Stresses on polyimide pipes under various loads are evaluated through finite element analysis. Design qualification and flight acceptance test loads are finalized based on NASA standards for human space missions. Deflection test plan done for flight acceptance of polyimide pipes in cryogenic upper stage. Finite element analysis was done to finalise the load requirements for each polyimide line. Design of split flanges done for deflection tests for different polyimide pipes. Evaluated load variation and deflections to be achieved for deflection test for flight acceptance condition for all the polyimide pipes identified for the flight acceptance test. Deflection tests were done for polyimide pipes and compared the results with the finite element results for a typical polyimide pipe. A good match is observed for load and deflections for prediction and testing. Polyimide pipes for the cryogenic upper stage of a human space mission have undergone flight acceptance tests successfully. Acknowledgements The authors gratefully acknowledge the academic selection committee of LPSC/ISRO for giving permission to present this paper in SICE2024. The support given by Shri. Vivek S. and Wariskhan is acknowledged here. Thanking Dr. Remya Balakrishnan and Shri. Nallaperumal A. M. of APD/VSSC for providing the information regarding polyimide pipe processing, and Shri. Sabareesh G. and Nandakumar S. of CST/IPRC for sharing the deflection test configuration. We acknowledge the continuous motivation and encouragement given by Shri. Viswanath for conceiving this technical paper. Thanks, are also due to the Director, LPSC, for permitting to publication of this paper. References Ansys User manual, Version 2020 R1. DuPont, Summary of properties of Kapton, 2022, EI-10142 (1/22). Harish Reddy D., Nallaperumal A M, R Muraleekrishnan, Impact of Non-Destructive Evaluation on the Quality of Multi-Layered Polyimide Pipelines for Cryogenic Application, Proceeding of NDT conference - 2016. Madheswaran G., S Ratheesh, Elizabeth John, Non-Destructive Evaluation of Polyimide Pipelines Used For Cryogenic Applications, Proceedings of National Seminar & Exhibition on Non-Destructive Evaluation, NDE 2014, Pune, December 4-6, 2014 (NDE-India 2014) Vol.20 No.6 (June 2015) - The e-Journal of Non-destructive Testing - ISSN 1435-4934. Niyas Ali S., 2014. Constitutive Modelling of Polyimide Pipeline for Cryogenic Applications, International Journal of Scientific & Engineering Research 5, Issue 7 Qiang Chen, Qingguo Sun, Jia Yan,Yunguang Cui, Lufeng Yang, Xiaojing Yang and Zhanjun Wu, 2024. Development and Recent Progress of Hoses for Cryogenic Liquid Transportation, DOI : 10.3390/polym16070905. Ralph R. Roe, Strength and life assessment requirements for liquid-fueled space propulsion system engines, NASA-STD-5012B, June 2016. Schwartzberg Fred R., Osgood Samuel H., Herzog Richard G, Knight Marvin, Cryogenic Materials Data Handbook, Volume II, Air Force Materials Laborartory, Ohio, AFML-TDR-64-280, July 1970. Sekhar Natraj,VK Ravindran, S Somanathan, N Rajkumar, SS Manna, R Sumangali and Dr. B Valsa, Ultrasonic and Acousto ultrasonic evaluation of polyimide pipes and its interface for Indian cryogenic rocket stages for space launch vehicles, Proceeding of NDT conference.