Procedure qualification of MAG welding wires for ultra-low temperature vessel welding

According to the design requirements of a large cryogenic vessel, the impact absorption energy of welded joints at-196℃ after stress relief heat treatment is ≥60J. Through the welding process evaluation test of domestic ER316LMnG welding wire and imported ER317Lmod welding wire, the results show that the tensile properties,impact absorption energy at-196℃, bending properties and intergranular corrosion properties of the welded joints all meet the technical requirements. In particular, the impact absorption energy at-196 ℃ can remain stable above 90J. It can be seen that,the two welding materials can be used for 304LN austenitic stainless ultra low temperature vessel welding.