Heat Input on GTAW (duplex)

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Can the heat input be calculated on GTAW, and if it is what it is the formula? Now do the parts need to be turning to calculate the heat input?
Reply:HuH?...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:The parts don't have to be turning, you just need to know that the travel speed will stay constant.Heat input is generally defined by the formula (A x V)/TSWhere A = Current (amps)V = Voltage (volts)TS = Travel Speed (mm/s)The value is normally quoted in kJ/mm.However, some of the energy generated by the arc fails to reach the weld pool because of radiation losses. To take these losses into account, the heat input formula is multiplied by a thermal efficiency factor related to the type of welding process used.The thermal efficiency factors are:Submerged arc: 1.0MIG, MMA and FCAW: 0.8TIG and plasma: 0.6 [1] Also, in case you don't know, with Duplex you need to keep an eye on the interpass temps.Hope this helps
Reply:(Volts x Amps x 60) / (Travel Speed x 1000) will give you KJ/in or KJ/mm.  If need be, multiply your final answer by your efficiency factor.  Or, for pulsed/waveform controlled power supplies, take your Energy/Bead Length, or (Power (joules per second) x arc time)/Bead Length.Cooling rates play as big, if not a greater role, than heat input in determining the ferrite/austenite balance in Duplex steels.  I have run heat inputs in excess of 100 KJ/in with certain processes without nitrogen mixes, and still retained greater than 35% ferrite.Last edited by Supe; 07-15-2011 at 07:58 AM.
Reply:Dear Friendsdoes any one can say heat input of TIG welding or arc welding is more? For keeping a minimum heat input which will be the best option? is there any thump rule for finding heat input of ARC and TIG welding at different current?Thanks
Reply:Originally Posted by anilmeleDear Friendsdoes any one can say heat input of TIG welding or arc welding is more? For keeping a minimum heat input which will be the best option? is there any thump rule for finding heat input of ARC and TIG welding at different current?Thanks