DCEP - DCEN Question

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NEWBIE question but for GTAW GMAW AND SMAWWhere is 2/3 of the heat located in them? Im going through my books and it says GTAW heat is in the Postive side but in GMAW it says the opposite can someone please explain im a little confused on this!
Reply:Originally Posted by ThaPirateNEWBIE question but for GTAW GMAW AND SMAWWhere is 2/3 of the heat located in them? Im going through my books and it says GTAW heat is in the Postive side but in GMAW it says the opposite can someone please explain im a little confused on this!
Reply:This is defidently something I gotta bring up with my teachers, My GTAW and GMAW Books say the opposite of each other! ! Thanks a ton I needed to clear this up before I went crazy
Reply:standard polarity = dcen =GTAWreverse polarity = dcep = GMAWPolarity helps control the amount of electrons available for the arc.Think of the size of the welding table and all the potential electrons on the surface.Strike an arc with the electrode positive and they all rush to the electrode. In TIG the tungsten will ball and melt off. In MIG you have a nice welding arc.With electrode negative you only have the electrons that can get through the tungsten.This way the tungsten will get hot but not melt off.
Reply:Like implied above, it is the impact of electrons that produces the majority of heat in the arc.  In TIG electrons flow to the workpiece (DCEN) and in MIG they flow to the wire (DCEP).  So TIG is easy to understand, by it may not be apparent why putting more heat to the wire in MIG is functional.  In MIG the wire is melted and deposited in the weld pool, thus transfering it's energy very efficiently.
Reply:Heat is concentrated on the positive side of the arc. So DCEN = more heat in work; DCEP = more heat in electrode.Edit: Like pulser stated above, in GMAW more heat is put into the wire. This is to melt the wire quickly and because the wire becomes part of the weld the heat from the wire is transferred to the work anyway. When you think of it that way the majority of the heat is transferred to the work. The same is true in SMAW and other consumable electrode arc welding processes.Last edited by emagray; 10-19-2010 at 09:49 AM.Weld Instructor