International Journal of Scientific & Technology Research

IJSTR@Facebook IJSTR@Twitter IJSTR@Linkedin
Home About Us Scope Editorial Board Blog/Latest News Contact Us

IJSTR >> Volume 3- Issue 6, June 2014 Edition

International Journal of Scientific & Technology Research  
International Journal of Scientific & Technology Research

Website: http://www.ijstr.org

ISSN 2277-8616

Design Of Welding Fixture For Head End Sub-Assembly Of Motor Case

[Full Text]



Naveen A M, V A Girish



Index Terms: Welding fixture, Maraging steel, Motor Case, Copper-Arsenic, Weld back-up support, head end sub-assembly.



Abstract: This paper deals with the design of the welding fixture for the head end sub-assembly of a rocket motor case. The head end sub-assembly consists of four parts namely Y-Ring, Dome, Igniter Boss and the Fore skirt ring that have to be welded to each other with a specified tolerance and weld quality. The material used in the manufacture of different parts of head end sub-assembly is Maraging steel which is one of the most commonly used material in the field of aerospace. All the welding processes are carried out in the presence of the Copper Arsenic back-up support bar to ensure the quality of weld is as per the requirement. The optimum thickness of the back-up support bar is determined and with in-process purging facility in the copper-arsenic bar ensure sound weld. Modeling of all the parts of head end sub-assembly and the welding fixture is carried out using UNIGRAPHICS NX8.0.



[1] S. Selvakumar “Clamping Force Optimization For Minimum Deformation of Workpiece by Dynamic Analysis of Workpiece-Fixture system” IISN 1818-4952. IDOSI 2010. pp 840-846

[2] A. Subhanand Rao , G. Venkata Rao , B. Nageswara Rao “ Effect of Long-Seam Mismatch on the Burst Pressure of Maraging Steel Rocket Motor Cases” Engineering Failure Analysis 12 (2005) pp 325-336.

[3] M. C. Mittal, B. R. Ghose “ An Analysis of Fracture Toughness in the HAZ of GTA Welded Maraging Steel ” Welding Research Supplement , November 1989,pp 457-461.

[4] Siva Sankara Raju R, Karun Kumar Y, Pragathi Kumar G “ Design and Analysis of Motor Casing by Using FEM Technique” IJEAT ISSN: 2249-8958, Volume-2,Issue-3, February 2013 pp 70-74.

[5] M. Varul , H. F. Muzafferoglu, U. C. Tapici “ The Effect of Welding Fixtures on Welding Distortion “ JAMME, Volume 20 ,Issue 1-2, Jan-Feb 2007 ,pp 511-514.

[6] Hui Wang , Yiming (Kevin) Rong “Case Based Reasoning Method For Computer Aided Welding Fixture Design”, ELSEVIER, Computer-Aided Design 40(2008) pp. 1121-1132.

[7] “18 percent Nickel Maraging Steels Engineering properties” Publication No. 4419 by Nickel Development Institute.

[8] Iain Boyle , Yiming Rong , David C. Brown “A Review and Analysis of Current Computer-aided Fixture Design Approaches" , ELSEVIER, Robotics and Computer –Integrated Manufacturing 27 (2011) pp.1-12.

[9] H. T. Sanchez “ Analysis and Compensation of Positional and Deformation Errors Using Integrated Fixturing Analysis in Flexible Machining Parts “ Springer-Verlag London Limited , pp. 241-252, Jan 2006.

[10] Patricio F. Mendez “New Trends In Welding in the Aeronautic Industry”, Massaachusetts Institute of Technology, Cambridge , MA 02139, USA, pp 1-15.

[11] F. Sikstrom , A. K. Christiansson , B. Lennartson “ Role of Fixture Forces on Distortion in Gas Tungsten Arc Welding – an Experimental and Modelling Approach” proc. IMechE Vol.225 Part B:J .Engineering Manufacture pp. 140-148.,August 2010.

[12] R. Scott Funderburk “ Concepts of welding Operation”

[13] G. R. Stoeckinger, R. A. Calabrese and R. F. Menaul “ Computerized Prediction of Heat Distribution in Welding Tooling” paper based on 48th Annual meet at Detroit during April 24-28.Science direct pp 14-26, Jan 1970.

[14] www.wikipedia.com/maragingsteel

[15] M. Estrems, H. T. Sanchez and F.Faura “ Influence of Fixtures on Dimensional Accuracy in Machining Processes” springer-2003,pp384-390.