Tech Tips: Self-Shielded Flux Cored Arc Welding (FCAW-S) Troubleshooting

hi I'm Dan Klein with the link electric welding school today we're going to go over some troubleshooting of flux-cored self shielded welds we're going to look at some of the different variables and how they affect the outcome of your weld and what we need to look at to help improve that the first rail but we're going to look at is wire feed speed what your feed speed is directly related to the current so the higher the wire feed speed the higher the welding current the lower the wire feed speed the lower the current so we've got our welding machines set for what would be considered a too low of a wire feed speed and you're going to notice the the transfer of the droplets is going to be more of a globular type transfer and we're not going to get complete coverage of the slagging system on top of the well and a lot of spatter so we're going to go ahead and make a weld and show you what it looks like when you've got too low of wire feed speed notice first of all it's very hard to get the little slag gets on there off and we do have a lot of spatter and remember we've said that wire feed speed is also the current solo on wire feed speed we have a very low current here as well so not much penetration into the base metal and an arrow type beam okay the next variable that we're going to look at for troubleshooting our flux-cored self shielded welds is too high of wire feed speed again we mentioned the wire feed speed is going to be is going to be our current and what's going to happen when we have too high a wire feed speed is you're going to notice the wire wants to keep stubbing so with that you can either do one of two things you either turn your wire feed speed down or you turn your voltage up to correct that so this world we're going to make now is an example of too high of wire feed speed so you could hear that stubbing of the wire now obviously that was an exaggerated high wire feed speed but that's something that you'll commonly see it could be due that level or it might not be that that you know that easily a seen now we're going to look at the effects of travel speed so what happens when you go too slow or when you go too fast the first well we're going to make is at too slow of a travel speed now we've set our machine for the factory recommended settings which is located under the door and we're going to be set at a wire feed speed of two and a half and a voltage setting of D and we're going to all we're going to do is change our travel speed first one again being too slow so we made our weld with too slow of a travel speed and if we look we can tell we've got a real buildup weld or a convex weld and it's also very wide and you also notice to the slag didn't quite cover properly on the weld as well the next world we're going to make is now we're going to go too fast we're going to increase the travel speed again we have not changed our machine settings all we're going to do is go faster than what's recommended for this particular well you also notice that I'm breaking the wire every time before I start that's a recommended practice for the self shielded flux-cored wires it'll get a little ball of silicon on the end and it'll insulate it and it will allow you to start very well so we'll just feed on a little bit and break it off and we'll get a better start so we just finished our flux-cored weld that is brand to fast and you can really see a difference between the first one we made which was too slow of a travel speed and then the second one that we made where we actually we've completely outran the puddle we didn't get the follow or the proper bead size that we want so we just need to slow down our travel speed to get the proper size as well the next variable we're going to look at for flux-cored self shielded troubleshooting would be the contact tip to work distance that's very important for flux-cored cells shielded wires for this particular wire that we're running which is o 35 and our 211 MP the suggested contact tip to work distance is a half inch to 5/8 which we've got here but I'm going to demonstrate what happens if you have too short of a contact tip to work distance and too long so the first wall that I'm going to make is going to be too short of a contact tip to work distance and you'll see uh several different things but one of them will be that we don't get the proper the preheating of the flux inside the wire and we won't get adequate coverage of that so we just made our weld with too short of a contact tip to work distance and like I said you'll notice that the slag had not covered the entire weld it didn't have time to preheat and you'll notice great down the middle it looks real dark that's because the slag was only on the edge of the weld so very important variable in a flux cored arc welding self shielded now we're going to show you too long of a contact tip to work distance so again recommended is a half inch to 5/8 we're going to take it over 5/8 and we're going to look and see what happens and your again we're going to notice a little bit of stubbing of the weld and it's not going to be wetting out very well now this world you'll notice that it it sounded a little different I was because with that longer contact tip to work distance you could see the wire was kind of hunting or going back and forth so we weren't getting very consistent feeding and you can almost tell that by the way that it made those little ripples in the weld there with just even a straight drag progression you could see how the wire was kind of hesitating every once in a while so make sure to maintain that half inch to 5/8 one important another important thing is polarity polarity is very important for flux-cored arc welding self shielded the recommended polarity for this wire that we're running Oh 35 and our 211 MP is DC negative a common mistake is that it is it's often ran on positive and a lot of times you don't realize what's going on so I'm going to demonstrate a weld on the wrong polarity which we're going to run it on DC positive and notice the difference in the arc so we just ran that weld on the wrong clarity we ran it on dc+ and if you notice we got a lot of spatter in large balls of spatter and we've got a fairly small weld as well so we definitely want to make sure that we make sure that we're on the correct polarity before we make the weld so I just made it well you saw what happened when I welded with the flux cord cells shielded on the wrong polarity remember the recommended polarity is dc- or straight polarity so now what we're going to do is we're going to go ahead and set up the machine for the correct polarity and we can reference up here it says for inner shield FCA wnr 211 MP it shows a diagram of the machine setup and there positive and the negative terminals so for DC electrode negative it's going to be the lead that's coming from the feeder is going to be put on to negative and then our work will actually be positive so we'll change these around so that is set up for DC electrode negative our wire from our feeder is hooked to our negative output stud and our work lead is hooked to our positive stud now one of the last things we talked about in troubleshooting our welds for flux cored cells shielded wire are going to be our angles now one of the rules that we talked about and we talked about it with stick welding is that there slag you drag so in the self shielded flux-cored process there is a slagging system so we want to make sure that we drag the electrode and that allows the slag to form behind the weld and it's lighter than the molten puddle and it will float to the top so if we push it a lot of times you'll take the chance of getting slag inclusions in your weld so make sure slag we drag now recommended angles we've got several different angles that we commonly refer to one of them is going to be our work angle work angle for this particular joint we could be ninety degrees but on a lap joint or a tea joint you want to be about forty-five to the joint and just a slight drag maybe five to ten degrees with this cell shielded flux-cored wire so very important that we maintain those those angles so we've got working --gel and we've got travel angle so now that we've covered some common areas of troubleshooting for flux-cored cell shielded welds we've covered our contact tip to work distance we covered our travel speed our wire feed speed and now we're going to put those all together for proper weld and we're going to try to make a weld with the correct settings and just drag it down the joint now we just finished our weld with the proper settings the proper contact tip the work distance travel speed wire feed speed and voltage and if you look we now have a consistent weld that's that's fairly uniform it's flat but you also notice that our slag coverage is very consistent across our whole weld if you remember before some of our variables if we were without within tolerance or without out of Tolerance it would not cover the whole weld so now we can take the slag and it will come off very easily and we get a nice shiny looking well so if you want more information about welding you can go to Lincoln electric calm you

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Keywords: lincolnelectrictv, lincoln electric, welding, welder, weld, lincoln, electric, fcaw, flux-cored, fcaw-s, electrode, wire, sp140t, dan klingman, tech tip, troubleshooting, Lincoln Electric, #WeldRed, #WeldRedNation, Welding, Weld, Welder, Fabrication

Id: iD7Y57gK3yU

Length: 13min 14sec (794 seconds)

Published: Wed Jan 02 2013