Challenging Experiences in the Usage of Stainless Steels in a Heavy Fabrication Industry

Abstract:

Stainless steels are regularly used as one of the preferred material of construction in the pressure vessels and heat exchangers manufactured by welding for process plants and energy sector at BHEL, Tiruchirappalli. They are considered mainly because of their corrosion resistance and high temperature suitability. But the practising welding engineers have to face innumerable challenges with stainless steel with regard to defects minimization, distortion control and dimensional stability on large and complex assemblies. Use of Nickel based filler wires or development of welding procedures simulating the true configuration of the product and by conducting specific tests and NDE are followed for weld defects control. Sequence welding, development of special fixtures, etc have come as handy options for welding distortion control of SS. Innovative inspection techniques for the certification of dimensions including geometrical tolerances especially on large constructions using SS welding and evolution of special Helium leak testing procedures for certain in-process checks in critical products are inevitable in the SS fabrication industry as a part of Quality Assurance programme. As a pioneer in SS fabrication, some of our challenging experiences pertaining to these three areas are discussed in this paper.

• Periodical: Advanced Materials Research (Volume 794)
• Pages: 316-331
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.794.316
• Online since: September 2013
• Authors: T. Gurunathan
• Keywords: Cladding, Concentricity, Creep, Distortion, Hard Facing, Inconel, Optical, Passivation, Profile, Radial Port, Sweeping, Template, Tube Sheet, UHV, Vacuum Cup, Vacuum Jacket

References

[1] American Society For Metals, Source Book on Stainless Steels, ASM, USA, (1976).

[2] T. Gurunathan, A.R. Subramanian, B. Sivasubramanian and V. Ganesan, Newer Techniques for the determination of extent of welding distortion and exact cladding thickness in large size dished heads, Technical Paper presented in International Welding Symposium, IWS 2K12, Mumbai, India. (2012).

[3] T. Gurunathan, S. Arunagiri and A.R. Subramanaian, Evolution of new measurement techniques for the large sized petals of main vessel, Technical Paper presented in National Welding Seminar, Trichy, India, (2000).

[4] T. Gurunathan, C. Rajakarthikeyan, O.P. Harikrishnan and Dr.K.G.K. Murti, Establishment of welding technology for the stainless steel baking channels ensuring distortion control and stringent Quality requirements, Technical Paper presented in National Welding Seminar, Chennai, India, (2002).