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Technical Information | FAQ | SMAW
Electrodes welding (SMAW)

  1. What type of electrode do I use for welding specific materials?
  2. Which stick electrode do I use to weld Aluminum parts?
  3. Which stainless steel electrode should I use?
  4. What thickness can I weld with a specific diameter of electrode?
  5. What is the difference between an E308L electrode and an E316L electrode?
  6. What are the electrical requirements for a 225 Amp welder?
  7. What is duty cycle?
  8. Do we have a chart showing the positions of use and applications of the different stick electrodes?
  9. Why is a welding machine AC or AC-DC?
  10. At what amperage should I set my machine?

1-What type of electrode do I use for welding specific materials? (top)
For general purpose welding the easiest electrode to use is the LA 7014 electrode. If the material is dirty or rusty the customer does not want to clean or grind the material, then LA Ultra 11 electrode is an excellent choice. For thin material the LA 6013 electrode is a good choice. When welding thin gauge with LA6013 tack the joint to keep it tight and if possible weld vertical down or downhill. For welding on trailers or parts subject to shock or impact such as cast steel machinery parts the LA ExcelarcMC 18 is a good choice for AC or DC use and LA7018 if the customer has a DC machine


2-Which stick electrode do I use to weld Aluminum parts? (top)
Blueshield MNRTM Lite is the aluminum-covered electrode. It should be used on Direct Current, electrode positive.


3-Which stainless steel electrode should I use? (top)
An E 309 or E309L should be used for welding stainless steel to carbon steel. An E308L or E316L can be used to weld type 304 base materials. Type E316L material should be welded with a type E316L electrode.


4-What thickness can I weld with a specific diameter of electrode? (top)
Normally the smaller diameters of electrodes 3/32 and 1/8 inch or 2.5mm and 3.2 mm are used for thin material, usually under 3/16 inch thick and for welding out of position. Thicker material and flat position welding permits the use of larger diameter electrodes.


5-What is the difference between an E308L electrode and an E316L electrode? (top)
The E 308L electrode is an alloy or mix of roughly 18%Chromium and 8%Nickel in Iron. The E316L electrode mix or alloy is essentially the same with 2-3% Molybdenum added to improve corrosion resistance.


6-What are the electrical requirements for a 225 Amp welder? (top)
The electrical requirements for welding machines are typically found on an information plate located on the front or back of the machine. A225 amp machine uses a 220-volt input and at maximum load draws slightly more than 40 amperes. The majority of these machines are typically not used at their maximum but in the range of 80-170 amperes depending on the diameter and type of electrode used.


7-What is duty cycle? (top)
All welding machines are tested and rated with a duty cycle. For example a machine might have a rating of 225 amperes at a 20% duty cycle. What this means is that in a 10-minute period the machine can operate for a total of 2 minutes at this rated amperage and the balance of the time or the other 8 minutes the machine must idle so that the cooling fan can cool the machine down. If the machine is used at lower amperage the duty cycle of the machine is higher. (You can weld for a longer time with lower amperages and have shorter cooling periods.)


8-Do we have a chart showing the positions of use and applications of the different stick electrodes? (top)
The Air LiquideTM Products Catalogue, page 46 is an excellent reference for the choice of covered or stick electrode to use.


9-Why is a welding machine AC or AC-DC? (top)
A welding machine takes high voltage low amperage from the wall or electrical panel and converts it into low voltage high amperage welding current. The lowest cost machines are typically AC or alternating current machines. DC machines have a smoother output and certain types of electrodes such as the E7018 types of electrodes function better on direct current (DC electrode positive).


10-At what amperage should I set my machine? (top)
The recommended amperage is quite often printed on the electrode box. If this information is not available there is a rule of thumb. Welding electrode sizes are based on the diameter of the rods metal core. Take the nominal diameter of the steel rod and convert this to thousandths of an inch. For every 1/1000 of an inch use 1 ampere of welding current. For example a 1/8-inch diameter electrode has a core wire of 1/8 inch or 0.125 inches (one hundred and twenty-five thousandths of an inch.) Set your machine for 125 amperes and you should roughly be in the ballpark.

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