How to identify MIG short-circuit process

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As an inspector, how can I tell if a MIG welder is using a short-circuiting process rather than a globular or spray process.  I've seen WPS's that state the transfer is globular but I ran across a WPS saying that it is a short-circuiting process, though the wire, gas and parameters are the same for both WPSs'.  I've had opinions as varied as "all MIG welding is a short-circuit process", another saying anything under 20 volts is short-circuit, and another saying the only way to tell is by the sound.  There must be a better way!
Reply:If you are looking at a weld procedure, then look at a few details. Use of CO2 or 75/25 gas is short circuit only. Higher voltages and wire feed speeds and use  of a higher argon blend 80/20 or 90/10 indicates a spray arc.
Reply:Don't you have to know this stuff before u become a welding inspector?  Spray transfer has a very specific appearance.  Put spray transfer in the search bar.  Thre are good threads with pics.  I also think its stupid that welding inspectors don't need an ounce oof welding experience to get their certsTiger Sales:  AHP Distributor    www.tigersalesco.comAHP200x; AHP 160ST; MM350P,  Spoolmatic 30A; Everlast PowerTig 185; Thermal Dynamics 60i plasma.  For Sale:  Cobra Mig 250 w/ Push-pull gun.  Lincoln Wirematic 250
Reply:When tuned just right is should sound like bacon frying in a cast iron skillet.
Reply:The ONLY true way to tell is to actually observe the welding arc, as each one has very distinct characteristics.  The problem with visual inspection of completed welds is that short-circuit can be very hard to distinguish from globular and occasionally spray can be made to look like short-circuit.Its much harder to tell the difference between SC and globular just by sound, and im sure someone could find a way to make spray sound like SC.THe transition voltages and currents are going to vary widely depending on wire diameter and type of shielding gas being used.  The WPS must state the mode of transfer to be used as one WPS will not cover a range of modes,Have we all gone mad?
Reply:Originally Posted by inspectorlarryI've seen WPS's that state the transfer is globular but I ran across a WPS saying that it is a short-circuiting process, though the wire, gas and parameters are the same for both WPSs'.
Reply:sn0 nailed it.  you pretty much have to watch it being welded.  I have had inspectors swear I was in sc when it was infact globular.  The sound is just one indication.  If you have a proud stickout then your sound will be different than if you have a short stickout.  I can hear a slight difference when I go from one to the other, but  just by listening to another welder, I can't tell if he is in globular or just isn't dialed in.One one wps I had the range and it was for globular.  For another weldment on the same job I had the same range and it was for shortarc.
Reply:Doesn't it also depend on position? I've experienced parameters which are definitely SC (ok) in flat/horizontal/vertical but which "go globular" (mess) when used overhead (until I reduced arc volts a bit)XMT304 (school)SP125+ (home)HF 4x6 BandsawGood judgement comes from experience and much of that comes from bad judgement.
Reply:In flat position welding, droplet detachment is aided by gravity.  When you switch to overhead, gravity is fighting droplet detachment meaning larger drops will form until sufficient electromagnetic forces have built up to push the glob off and across the joint.  This is why you saw a chance in transfer mode without changing any of the parameters.Have we all gone mad?