Improved ductility of type 347L overlay weld with low Si content for hydrogen service pressure vessels

摘要

In petroleum pressure vessels such as hydrogesulfurization reactors, crackignoccurs in gasket groove and internal attachment overlay welds due to a combined effect of sigma phase formation during post weld heat treatment (PWHT) and subsequent hydrogen embrittlement.Since Si has a strong tendency to promote sigma phase formation, Type 347L overlay weld with low Si content was made, and the effect of Si content on the embrittlement was examined.