A study on the optimization of manufacturing processes of double wall bellows for dual fuel engine II - Optimization of welding process -

Title & Authors
A study on the optimization of manufacturing processes of double wall bellows for dual fuel engine II - Optimization of welding process -
Kim, Pyung-Su; Kim, Jong-Do; Song, Moo-Keun;

Abstract
Production processes of double wall bellows can be roughly categorized into two steps. In the first step, inner and outer bellows are made of STS316L in austenite stainless steel due to their excellent formability and corrosion resistance. In the second step, the double wall bellows are manufactured using the welding method with both the inner and outer bellows. The microstructure and defects of each weldment are observed to ensure the reliability of bellows since weldment is a highly vulnerable part, which can crack and fracture when bellows are formed or used. In this study, optimum welding conditions were derived from the analysis of microstructure and inspection of weldment of bellows that were produced using various welding procedure. Moreover, the mechanical properties were evaluated through hardness measurement of substrate, weldment and the heat-affected zone.
Keywords
Double wall bellows;Weldment;Microstructure;Mechanical properties;
Language
Korean
Cited by
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