I have just got a shutdown to do for Amec the job is 316l pipework but there is 904L hubs on the end . Will i need to run a new procedures. What tig wire would i use.
From the nature of the question(s) you are asking, I would recommend you qualify a WPS (welding procedure specification). Both materials are weldable. What is the environment and application? What type of weld - groove, fillet,.... The application would dictate filler metal selection.
The environment will drive filler selection. I would guess that you will either use 904L or 317L as filler. You will want to be careful about weld ferrite, 904L welds can have zero ferrite and cracking can be an issue.
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