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I tried posting this several weeks ago, and couldn't figure out how to resize to fit, It became much clearer when I read the instructions for the digital camera!!! Left to right the gases used were as follows: C-10 (90 Arg 10 C02)Moongon (Stargon 90 Arg, 8 Co2, 2 Oxy) C-25, and M5 or O5 which is 95 Arg 5 Oxy. All welds were ran in the spray transfer mode, and yes you can get into a spray with C-25 gas if you have a machine that will put out over 32 volts. Note the voltage difference with M5 gas, this gas will transition to a spray transfer at lower voltages than the other gases. The penetration was the best with the C10, with Moongon, and C-25 next, M5 gave us the least penetration, it doesn't show up in the picture very well, but the penetration with the M5 gas was very shallow. I set the parameters high enough with every gas to give a quiet spray sound, (which you don't want) and then backed off a bit to give just a little crackle. If you run in spray mode and your arc is very quiet, you run the risk of undercut, as well as lack of fusion due to the arc length increasing with the higher parameters. I ran these samples for a shielding gases seminar I put on for a blacksmith/weldshop convention. As soon as I can find some thick (1/4" and 3/8") alum scrap, I'll post some pics comparing mig welds with straight argon, versus an argon helium mix. Parameters for the steel welds were as follows: C-10 GasWire feed speed: 280 IPMVoltage: 29Amps: 325Moongon Gas:Wire Feed Speed: 280 IPMVoltage 29Amps: 315C-25 Gas:Wire Feed Speed: 280 IPMVoltage: 33Amps: 300M5 Gas:Wire Feed Speed: 280 IPMVoltage: 26 VoltsAmps:320 Attached ImagesLast edited by ss42768; 04-01-2007 at 12:50 AM.
Reply:Extremely nice. A ASSume the wire was .045? .052?Thank You DavidReal world weldin. When I grow up I want to be a tig weldor.
Reply:Originally Posted by ss42768I set the parameters high enough with every gas to give a quiet spray sound, (which you don't want) and then backed off a bit to give just a little crackle. If you run in spray mode and your arc is very quiet, you run the risk of undercut, as well as lack of fusion due to the arc length increasing with the higher parameters.
Reply:I am going to try to spray with .035 wire and C/25 because I have it and my invertec v350 goes up to 45 volts CV. I have an 80 Cf bottle of 92Ar/ 8C02 on order to try that too. 98 AR and 2% O2 worked fine, but could not be used for short arc which I do a lot of.Thanks for the info.DavidReal world weldin. When I grow up I want to be a tig weldor.
Reply:Originally Posted by David RI am going to try to spray with .035 wire and C/25
Reply:What is the definition of, and parameters surrounding "silent spray"??
Reply:Same as a SBD I'd guess. Nothing much to indicate the process but the results! Craftsman 230a Buzz-box, Lincoln 140T & 180T, Century K2789, PUROX W202 O/A14" cheapo chop saw that cuts straight and square!A toolbox of the cheapest Chinese tools money can buy"Real" tools all old reliable Husky/Craftsman/Proto stuff
Reply:Originally Posted by ss42768I tried posting this several weeks ago, and couldn't figure out how to resize to fit, It became much clearer when I read the instructions for the digital camera!!! Left to right the gases used were as follows: C-10 (90 Arg 10 C02)Moongon (Stargon 90 Arg, 8 Co2, 2 Oxy) C-25, and M5 or O5 which is 95 Arg 5 Oxy. All welds were ran in the spray transfer mode, and yes you can get into a spray with C-25 gas if you have a machine that will put out over 32 volts.
Reply:Could you do it with straight CO2? That´d be nice =)Thanks for the pics thouMy Babies: HF Drill pressHF Pipe Bender3 4.5" Black and Decker angle grindersLincoln Electric PROMIG 175that´s it!
Reply:Whoa there Tensaiteki!!! All I said was you "run the risk" of undercut and lack of fusion if you run in a quiet spray mode. You can weld however you'd like, I prefer to run the way I like and was taught, by a 30 year CWI/CWE instructor. I dug out one of my old textbooks, here's the author's opinion on "quiet spray" versus "intermittent crackle""When the spray transfer voltage is set too high the result is a long arc length which produces a whoosh crackle free, quiet spray sound, this quiet spray sound means the stream of weld is transferred uninterrupted from the electrode tip to the weld. A long arc length can result in too much energy on the weld surface and not enough energy in the metal welded. The long arc with the resulting fluid weld adds to weld burn through potential on thin parts and creates undercut potential for any weld. A long spray arc can also be uncomfortable for the welder as the heat generated is absorbed by the glove and hand, likewise a long arc can also pull oxygen and nitrogen from the surrounding atmosphere into the weld, adding potential for porosity""To set the optimum spray transfer weld voltage, start out with the spray voltage set too high resulting in a quiet spray sound. Then reduce the voltage in increments of one volt, as the voltage is lowered the electrode wire tip will edge closer to the weld. When the electrode tip comes in close proximity to the weld (.050 to .060) the spray weld stream will occasionally be in contact with both the weld and electrode. The resulting weld and electrode contact creates intermittent short circuit disruptions of the spray transfer stream. A slight decrease in the weld voltage and the short circuits in the weld stream create a rapid consistent crackle sound. Dependig upon the application, a sound in which the crackle is either intermittent or consistent shows the weld voltage is optimum. For parts less than 3/16" or for vertical down spray welds use the lowest weld voltage, this produces a rapid almost harsh consistent crackle sound. For parts 1/4" and up, the larger weld area needs higher weld voltage, that should result in an intermittent crackle mixed in with the quiet spray"Tensaiteki: I as well prefer spray transfer, just not as quiet as you do. Elvergon: no, straight CO2 won't get you into spray transfer, with CO2 you get short circuit and globular.David R: Wire was .045 ER70S6, as far as getting into spray with C-25, yes C-25 would not be my optimum pick if I wanted to run in spray transfer all day, but if you have a machine that can run above 32-33 volts, give it a try.
Reply:I agree with ss42768, in general, the long arc length of a "pure hissing" spray transfer can cause problems with lack of fusion and irregular welds, particularly in tight joints and at higher travel speed. As with any arc process, as the arc gets longer, it also increases greatly in diameter, so the heating from the arc is less focused/concentrated.
Reply:It works with C/25. .035, 700 ipm, 34 volts. It sprayed but the arc was pretty long. I tried it at 450 ipm and about the same. I blew a 1/4" hole in the edge of 5/16 plate. Lower voltage and it was crackling with spatter. 35 volts made a longer silent arc. Some serious heat. Harder to control than 98/2.David
Reply:One thing I have been told about M5, I have no experience with it myself, but I was in a friends shop, that used to be his dad's welding shop, and he's been welding all his life. I noticed the M5 gas on one of his machines in the shop, and asked why he had that.He said they used it for tractor loaders, because the weld didn't crystalize, so it would hold up better to the constant flexing a loader under goes better than with CO2.
Reply:Originally Posted by AntiblingHe said they used it for tractor loaders, because the weld didn't crystallize, so it would hold up better to the constant flexing a loader under goes better than with CO2.
Reply:Tensaiteki, good point about the term "crystallized", it is very common for people to misuse this expression when talking about a metal fracture.All metals have a crystalline structure. Sometimes the grain structure is so fine it can only be seen under magnification of a polished and acid etched surface. Very large metal grains can sometimes be seen with the unaided eye on the surface of brass hand railings and certainly on galvanized (zinc) coatings.It is inaccurate and misinformed to say that a fractured piece of metal or a weld has failed because it has "crystallized". This description comes about because a brittle fracture is sometimes associated with large grain size and the fracture follows a path along the grain boundaries leaving a faceted surface that shows the "crystalline" structure of the metal.Heating and welding of metals can cause grain growth and loss of toughness that may lead to a brittle fracture that looks "crystallized", and this description may be in important indicator of type of failure, but saying the weld failed because it "crystallized" is not accurate.
Reply:For a true spray transfer, whether axial spray or pulse spray, you must run a gas with a minimum of 80% argon. 90/10 works very well for spray using .035 or .045 wire. |
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发表于 2021-9-1 00:32:19