Welding gasses for MIG and TIG explained

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Hi all, I am currently in the process of getting a replacement bottle of my usual gas mix and the LWS  guy said he can't get anymore of it which i thought that was odd as it is a popular tri-mix gas, (maybe he didn't want to stock that one anymore),  any way, this left me with no option but to research for a different mixture that would be suitable.  As my welding covers thick to thin plate mild steel, I wanted a sort of general one gas mix which would cover as as many welding situations (plate thickness wise) as possible without having to get multiple different gas mixes. Over here in Oz we can't buy the big bottles outright and can only rent them, which works out quite expensive. Whilst doing the search on the different types of mixes from the various manufacturers I came across this excellent article by BOC on the various different gasses and the effects that different gasses and mixtures have on the welds, both in TIG and MIG with the welds done buy a robot so no human intervention or error to cloud the results. It explains their gasses and has pictures of the welds, the various penetrations and using different metals.Once you find out the composition of the gas mix which suits your requirements you could track down an equivalent from any supplier. This document would be of benefit to all those members who ask about welding gasses, ie; Why can't I use straight argon for mild steel????? etc.Anyway I thought it was a very good informative read, I also found a supplier who has that gas mix that I wanted and was cheaper by about 30% and would deliver and exchange bottles for free.  So in the morning I will be switching my supplier. It's a 1.5mb download and the download link is: https://boc.com.au/boc_sp/downloads/...re_AUS_v12.pdfMiller Auto Invision 456 + S-62 wire feederC6240B1 Gap bed lathe16 ft3 air compressor16 speed pedestal drillHafco BS-912 Bandsaw
Reply:Thanks mateShould be a StickyEd Conleyhttp://www.screamingbroccoli.com/MM252MM211 (Sold)Passport Plus & Spool gunLincoln SP135 Plus- (Gone to a good home)Klutch 120v Plasma cutterSO 2020 benderBeer in the fridge
Reply:Originally Posted by Broccoli1Should be a Sticky
Reply:Suggestion to also see:http://www.esabna.com/EUWeb/MIG_handbook/592mig1_1.htmand especiallyhttp://www.esabna.com/EUWeb/MIG_handbook/592mig4_1.htmAnother overview from Lincoln about GMAW, including shielding gases:http://content.lincolnelectric.com/p...ture/c4200.pdf  The best laid schemes ... Gang oft agley ...
Reply:Thanks ZTFab for that quick response to make it a sticky.  Some of us old newbies like that informative stuff.Nctox,  Stickmate LX  235AC/160DC  HH210
Reply:Here's another good one for shielding gas selection including some general info about GMAW and filler wire as well.GMAW welding gases and info.pdfhttp://all-a-cart.comWelding Cart Kits and accessories
Reply:You can indeed buy the bottles outright (at least in Sydney). I have.http://www.speedgas.com.au/home.html__________________________________________________  _I could not care less where anything is made. I don't fall for the myth that locally made is 'better'. If I think something is good value for ME, I'll buy it. That said, I do like European quality
Reply:I guess you could get by with one gas but I can't imagine only one gas in my shop...It would make things VERY difficult and at best compromise quality......  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Anyone dealt with Matheson TriGas?  Specifically their APN-7 mix that is targeted at replacing argon/helium mixture for alumium TIG welding?This is what my Matheson Rep/Sales person gave me:http://www.mathesongas.com/industria...SON-Select.pdfand here is a slideshow that they gave me in print:http://www.slideshare.net/mathesonga...n-welding?ref=They can only get it in the large 300+ ft³ tanks, but I was hoping to get some input on it if anyone has used it.Last edited by Oscar; 06-19-2012 at 03:22 PM.
Reply:No, I have not heard of it. It makes me wonder though.....in college we were taught that we needed to shield the weldment from our atmosphere. Well, our atmosphere is mostly nitrogen, and about 21%oxygen. Why would you dope shielding gas with nitrogen? It is already in the air.Lincoln Power Mig 210MP MIGLincoln Power Mig 350MP - MIG and Push-PullLincoln TIG 300-300Lincoln Hobby-Weld 110v  Thanks JLAMESCK TIG TORCH, gas diffuser, pyrex cupThermal Dynamics Cutmaster 101My brain
Reply:Indeed you are very right that we are required to protect the weldments from atmospheric gasese and it sounds hilarious to shield it with nitrigen when it is already present in air.
Reply:A three-year research program focused on the application of advanced processes for P92 pipe welding was started in March 2011.The research program include the production of P92 pipe welds with the narrow-gap TIG (NG TIG), TOPTIG, variable-polarity submerged-arc (VP SAW), flux-cored (FCAW) and electron beam (EB) welding processes. NDT/mechanical testing of the narrow-gap TIG has been recently completed with successful results. Following these, creep testing is planned to determine their high-temperature properties.Process parameters to be applied when welding P92. The following were selected:Single-pass layer TIG welding techniqueNarrow groove joint 9mm wide with a 2° slope, accounting for cross seam shrinkage, enabling the maintenance of a constant groove width after each welding passThe use of pure argon welding gas, known for its universal availability
Reply:From where can I buy the welding gas..!what instruments are necessary to use it...?http://www.plagiarism-checker.me/
Reply:Originally Posted by ZTFabHere's another good one for shielding gas selection including some general info about GMAW and filler wire as well.GMAW welding gases and info.pdf
Reply:The reference to BOC gases is no longer valid.  Anyone know the new url for this information?
Reply:http://www.coregas.com/images/pdfs/s...on%20chart.pdfThen search their safety data sheets for the mixes of the gaseshttp://msds.chemalert.com/default.aspx e.g. search for CoreGas to bring up all the CoreGas products, ShieldPro for those etc.
Reply:I think this is it? Haven't looked at it yet but looks like a similar name....https://www.google.ca/url?sa=t&sourc...6Ovro4zqfBb0VQ
Reply:That's a good one!
Reply:Originally Posted by mookinshttp://www.coregas.com/images/pdfs/s...on%20chart.pdfThen search their safety data sheets for the mixes of the gaseshttp://msds.chemalert.com/default.aspx e.g. search for CoreGas to bring up all the CoreGas products, ShieldPro for those etc.
Reply:Does anyone have the PDF from the link that Ed posted originally?Old Welders (at work)Miller Deltaweld 452Miller Syncrowave 250Lincoln 180c powermig Current Welders (at work)Millermatic 252Millermatic 350 Miller Syncrowave 250DXMy Welders CE Dual Mig 170CE Inverter Arc/Tig
Reply:Originally Posted by strokedbroncoDoes anyone have the PDF from the link that Ed posted originally?
Reply:Thanks Sedly...that worked! You were right though....definitely slow to load!Old Welders (at work)Miller Deltaweld 452Miller Syncrowave 250Lincoln 180c powermig Current Welders (at work)Millermatic 252Millermatic 350 Miller Syncrowave 250DXMy Welders CE Dual Mig 170CE Inverter Arc/Tig
Reply:Hi Joker11,  That's actually a good point, I never thought about why do we need shielding gas since the atmosphere consists of primarily Nitrogen....until I read your post that is.  The reason shielding gas is required is to protect the weld from Oxygen and water vapor.  It is the Oxygen and water vapor that compromise the welds.  Now given that, I guess if one was to weld in space, there would be no need for shielding gas, but there would definitely be a cooling problem of welds due to extreme low temps.  Bottoms up.A plumber is an adventurer who traces leaky pipes to their sourceChilliwack Plumbing and Hot Water Tanks
Reply:RobmanQ, if you wanted to TIG in space, you would still need a knoble (ion) gas for the plasma to melt metals. Ive never welded in space but Im thinking stick or flux core would be the method or some new type of arc. It wouldnt be practical to take Argon or Helium into space at the present time. Maybee in the future they will have semi shuttles tho. I have a question: has Neon , Xenon or any of the other knoble gases been tried for TIG or MIG ?
Reply:Originally Posted by InsanerideRobmanQ, if you wanted to TIG in space, you would still need a knoble (ion) gas for the plasma to melt metals. Ive never welded in space but Im thinking stick or flux core would be the method or some new type of arc. It wouldnt be practical to take Argon or Helium into space at the present time. Maybee in the future they will have semi shuttles tho. I have a question: has Neon , Xenon or any of the other knoble gases been tried for TIG or MIG ?Ok thanks HT2. My spelling has gotten worse in recent years. I still have to ask tho; why isnt Neon a popular weld gas? Xenon, Krypton and Radon are also Noble.BTW,  altho Nitrogen isnt noble, it will ionize and melt metal. It has been mentioned that Nitrogen is not good for the weld tho. The Noble gases wont react like nitrogen or oxygen with metal because there valence band is full.Last edited by Insaneride; 01-14-2017 at 10:56 AM.
Reply:I never looked much my self but I have heard that neon is something like 100x the price of argon.old Miller spectrum 625 Lincoln SP-135 T, CO2+0.025 wireMiller model 250 and WP-18V torchCraftsman 100amp AC/DC and WP-17V torchCentury 115-004 HF arc stabilizerHome made 4 transformer spot welderHome made alternator welder
Reply:Originally Posted by InsanerideOk thanks HT2. My spelling has gotten worse in recent years. I still have to ask tho; why isnt Neon a popular weld gas? Xenon, Krypton and Radon are also Noble.
Reply:Originally Posted by mad welder 4I never looked much my self but I have heard that neon is something like 100x the price of argon.
Reply:Heres some ion energies I had saved. Ionization Energies (eV) of Atoms and IonsPrepared for IAU Symposium 210 (Uppsala Sweden, June 2002)Values for first and second spectra are from NIST (II's courtesy of Jean Sansonetti), except for At I, from HCP. Most other entries are from Handbook of Chemistry and Physics, 3rd electronic edition. Additional entries are from Dappen (AQ IV, 2000) or Cowan (1987). Most of the Dappen values are given to the nearest electron volt, though In IV, Tl IV, and At I are given to the tenth of an eV. Some entries for the REE third and fourth spectra were given by Cowan to the hundredth of an eV, and those values are reproduced here, though they are surely uncertain. It is amazing that we know the second ionization energies of several 5d elements only to the nearest eV. Y II is from Phys. Scr. 44, 226 (1991).Hydrogen H       1 13.5984Helium He        2 24.5874  54.417760Lithium Li       3 5.3917   75.6400    122.45429Beryllium Be     4 9.3227   18.21114   153.89661 217.71865Boron B          5 8.2980   25.1548     37.93064 259.37521 340.22580Carbon C         6 11.2603  24.3833     47.8878   64.4939  392.087Nitrogen N       7 14.5341  29.6013     47.44924  77.4735   97.8902Oxygen O         8 13.6181  35.1211     54.9355   77.41353 113.8990Fluorine F       9 17.4228  34.9708     62.7084   87.1398  114.2428Neon Ne         10 21.5646  40.96296    63.45     97.12    126.21Sodium Na       11 5.1391   47.2864     71.6200   98.91    138.40Magnesium Mg    12 7.6462   15.03527    80.1437  109.2655  141.27Aluminum Al     13 5.9858   18.82855    28.44765 119.992   153.825Silicon Si      14 8.1517   16.34584    33.49302  45.14181 166.767Phosphorus P    15 10.4867  19.7695     30.2027   51.4439   65.0251Sulfur S        16 10.3600  23.33788    34.79     47.222    72.5945Chlorine Cl     17 12.9676  23.8136     39.61     53.4652   67.8Argon Ar        18 15.7596  27.62965    40.74     59.81     75.02Potassium K     19 4.3407   31.63       45.806    60.91     82.66Calcium Ca      20 6.1132   11.87172    50.9131   67.27     84.50Scandium Sc     21 6.5615   12.79977    24.75666  73.4894   91.65Titanium Ti     22 6.8281   13.5755     27.4917   43.2672   99.30Vanadium V      23 6.7462   14.618      29.311    46.709    65.2817Chromium Cr     24 6.7665   16.4857     30.96     49.16     69.46Manganese Mn    25 7.4340   15.6400     33.668    51.2      72.4Iron Fe         26 7.9024   16.1877     30.652    54.8      75.0Cobalt CO       27 7.8810   17.084      33.50     51.3      79.5Nickel Ni       28 7.6398   18.16884    35.19     54.9      76.06Copper Cu       29 7.7264   20.2924     36.841    57.38     79.8Zinc Zn         30 9.3942   17.96439    39.723    59.4      82.6Gallium Ga      31 5.9993   20.51514    30.71     64        87Germanium Ge    32 7.8994   15.93461    34.2241   45.7131   93.5Arsenic As      33 9.7886   18.5892     28.351    50.13     62.63Selenium Se     34 9.7524   21.19       30.8204   42.9450   68.3Bromine Br      35 11.8138  21.591      36.       47.3      59.7     Krypton Kr      36 13.9996  24.35984    36.950    52.5      64.7Rubidium Rb     37 4.1771   27.2895     40        52.6      71.0Strontium Sr    38 5.6949   11.0301     42.89     57        71.6Yttrium Y       39 6.2171   12.22       20.52     60.597    77.0Zirconium Zr    40 6.6339   13.1        22.99     34.34     80.348Niobium Nb      41 6.7589   14.0        25.04     38.3      50.55Molybdenum Mo   42 7.0924   16.16       27.13     46.4      54.49Technetium Tc   43 7.28     15.26       29.54     46        55Ruthenium Ru    44 7.3605   16.76       28.47     50        60Rhodium Rh      45 7.4589   18.08       31.06     48        65Palladium Pd    46 8.3369   19.43       32.93     53        62Silver Ag       47 7.5762   21.47746    34.83     56        68Cadmium Cd      48 8.9938   16.90831    37.48     59        72Indium In       49 5.7864   18.8703     28.03     54.4      77Tin Sn          50 7.3439   14.6322     30.50260  40.73502  72.28Antimony Sb     51 8.6084   16.63       25.3      44.2      56Tellurium Te    52 9.0096   18.6        27.96     37.41     58.75Iodine I        53 10.4513  19.1313     33        42        66Xenon Xe        54 12.1298  20.9750     32.1230   46        57Cesium Cs       55 3.8939   23.15744    35        46        62Barium Ba       56 5.2117   10.00383    35.84     49        62Lanthanum La    57 5.5769   11.059      19.1773   49.95     61.6Cerium Ce       58 5.5387   10.85       20.198    36.758    65.55Praseodymium Pr 59 5.473    10.55       21.624    38.98     57.53Neodymium Nd    60 5.5250   10.72       22.1      40.4      60.00Promethium Pm   61 5.582    10.90       22.3      41.1      61.69Samarium Sm     62 5.6436   11.07       23.4      41.4      62.66Europium Eu     63 5.6704   11.25       24.92     42.7      63.23Gadolinium Gd   64 6.1501   12.09       20.63     44.0      64.76Terbium Tb      65 5.8638   11.52       21.91     39.79     66.46Dysprosium Dy   66 5.9389   11.67       22.8      41.47     62.08Holmium Ho      67 6.0215   11.80       22.84     42.5      63.93Erbium Er       68 6.1077   11.93       22.74     42.7      65.10Thulium Tm      69 6.1843   12.05       23.68     42.7      65.42Ytterbium Yb    70 6.2542   12.176      25.05     43.56     65.58Lutetium Lu     71 5.4259   13.9        20.9594   45.25     66.8Hafnium Hf      72 6.8251   15          23.3      33.33     68.38Tantalum Ta     73 7.5496   16          22        33        45Tungsten W      74 7.8640   16.1        24        35        48Rhenium Re      75 7.8335   17          26        38        51Osmium Os       76 8.4382   17          25        40        54Iridium Ir      77 8.9670   17          27        39        57Platinum Pt     78 8.9587   18.563      28        41        55Gold Au         79 9.2255   20.20       30        44        58Mercury Hg      80 10.4375  18.7568     34.2      46        61Thallium Tl     81 6.1082   20.4283     29.83     50.7      64Lead Pb         82 7.4167   15.03248    31.9373   42.32     68.8Bismuth Bi      83 7.2856   16.703      25.56     45.3      56.0Polonium Po     84 8.417 ?  19          27        38        61Astatine At     85 9.3      20          29        41        51Radon Rn        86 10.7485  21          29        44        55Francium Fr     87 4.0727   22          33        43        59Radium Ra       88 5.2784   10.14715    34        46        58Actinium Ac     89 5.17     11.75       20        49        62Thorium Th      90 6.3067   11.9        20.0      28.8      65Protactinium Pa 91 5.89Uranium U       92 6.1941   10.6Neptunium Np    93 6.2657Plutonium Pu    94 6.0262   11.2Americium Am    95 5.9738Curium Cm       96 5.9915It looks like Neon is hotter than Argon. Argon needs 18 volts compared to 22 for Neon. I was thinking Neon was 10 volts but its actually number ten on the list. Helium is number two but needs 25 volts to ionize.
Reply:Originally Posted by Insaneride....why isnt Neon a popular weld gas? Xenon, Krypton and Radon are also Noble....
Reply:My question is answered . Thanks .
Reply:The various links given in the earlier postings seem to be broken.I have found this  http://coregas.com.au/public/images/...plications.pdfHope it helpsKen
Reply:Technical college presentation (with references): "Chemical Reactions and Metal Flow in Welding" --http://eng.sut.ac.th/metal/images/st...%20welding.pdf