Welding requirements for special grades of metal.

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Good morning all,I need to weld 2 flanges to a pipe, all of which are 347H material which are heat treated according to the following specs:-  Forgings shall be stabilised heat treated within a temperature range of 870 °C to 900 °C (1600 °F to 1650 °F) for 4 hours subsequent to the solution heat treatment.The question I hope someone can answer is what welding electrode can I use to weld these items together?I thank everyone in advance for your help as I am a new engineer!
Reply:Welcome!What is the application?Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Hi Shovelon, thank you for your quick reply!This is to be used for a high temperature cracked gas probe with operating temperatures of around 550 degrees celcius. We are need to weld these together but we are afraid we may use the wrong electrode. Our client has not given us any clear electrode to use.
Reply:do you have to follow particular codes?Welding this without a (qualified) WPS is a bit suspicious.you'll probably want a high-alloyed rod with low ferrite number and some Mo or Nb stabilizing (which basically is a 347 rod)Last edited by kingnero; 05-20-2014 at 05:52 AM.
Reply:Hey new engineer,Your assignment is to determine the existing parent materials and the service conditions of the part(s) in question, then research for any existing material or process 'Codes' that must be followed for materials, service conditions, and fabrication or repair, and then to determine the appropriate weld filler(s) and processes that are appropriate.'Processes' include preparation of workpieces, possible welding processes, and post-weld processing such as required or recommended inspection processes and possible post-weld heat treatment.hint:  The 'big' weld filler manufacturers as well as multiple welding Codes list recommendations and/or requirements for processes and fillers to be used.  Check catalogs/literature from ESAB, Sandvik, Lincoln, Harris, Techalloy, McKay, Hobart, Stoody, UTP and the AWS and API, to name just a few.   The best laid schemes ... Gang oft agley ...
Reply:This is something I have no clue about, but I remember some 347 turbine exhaust parts being welded with inconel 625, I think?Last edited by Advan; 05-20-2014 at 11:15 AM.
Reply:You can buy ER347 in lots of places, should give matching metallurgy.Experience is something you get right after you need it
Reply:Thank you all for your help! We have determined 347H to be used to weld.