could consumables causes unstable arc of MIG welding?

• https://www.linkedin.com/groups/122787/122787-6263710447417978884
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• Joe Balcerak Out of spec consumables (tips OR wire). Worn tips, clogged nozzles, or gas diffusors can all cause problems with the MIG process. It could be arc blow, or a poor ground too. 
  A little more info would be helpful.

  
  

• Joe Balcerak Also.............a simple thing, like not tightening weld tips, can cause major headaches.

  
  

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  Marco Gosparini Hi Joe,
  I work for a company that produces welding wires. Our customer usually buys ER 110 S- G and he has never had any problems with our product. Last week we handed him a supply of this new heat material and he says that with this heat it makes it difficult to set the welding parameters and has an unstable arc. If he uses the heat previously provided, he has no problems.
  The material from the chemical and metallurgical point of view it is conform to the standard AWS 5.28. 
  Is there anything in the material that causes these problems?
  Thanks

• Joe Balcerak I guess I'd start with running off a 5 meter length of wire and use a micrometer on it every 20 to 25 centimeters. Make sure the diameter is consistent. 
  Did he swap out a gas cylinder at the same time? Do they change torch liners at regular intervals? You have a tough one there.

  
  

• Joe Balcerak Any chance that the spool is cross-wound?

  
  

• Steven Meckstroth A problem that get blamed on wire, is operator over tightening feed drive rolls.

  
  

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  Niekie Jooste There could obviously be a number of issues on the customer's side regarding the machine set-up. If we assume that the customer has done his own in-house checks and the problem really does lie with your wire, then there are not too many possibilities for what could be wrong with the wire. Small changes in the chemical composition between heats should not have much of an effect. I would suggest that there is something wrong with the dimensional tolerances on the wire, or the "cast and helix". Did you do the necessary checks according to A5.28 in this regard? If you did, it may be possible that you had some problem in your production process that resulted in slight variances in the amount of cold work of that specific heat of wire. This could result in diameter fluctuations, kinks forming as it feeds through the feed rollers and variations in the resistivity of the wire. Is the surface finish good?

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  Lisa Moran cast and helix off, over lap of wire, center bursts, all kinds of problems..

  
  

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  Marco Gosparini Thank you all!!!
  
  @Joe the wire is within the diameter tolerances established by the standard, I'm sure! 
  I'm also sure that they change torch liners at regular intervals and the spool is not cross-wound
  
  @Niekie Jooste I agree with you about the small changes in the chemical composition. 
  I checked dimensional tolerances, cast and helix on the wire and are conforming
  
  @ Lisa Moran What do you mean when you talk about over lap of wire?

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  Sebastián Sierro Marcos, have you checked the surface of the Wire? Roughness, copper adherence, cleaning, rest of drawing soaps. According with my experience in the welding wire manufacturing, all these characteristics have a great influence in the arc stability.

  
  

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  Alan Mayfield I also used to be involved in making welding wires. Some elements in the steel have a profound effect on welding characteristics. Two different casts / heats of steel can both be in spec yet produce very different arc properties. The specs were written primarily to produce a weld of a certain strength etc.

  
  

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  Jason Rebarchik Like others have stated, surface condition can make a huge difference eventhough the chemical composition of the wire may be the same/similar to previous lots. As Sebastian pointed out about soap condition, I had a similar experience at the new year involving drawing lubes on stainless weld wire. The weld parameters we had now produced a cold weld and loss of arc occurances went up. Changed the wire drum to a different lot and it went away. After some experimentation, the supplier and I found a film on wire to be the culprit. If the wire is ok, and obvious things like liners and tips are changed, I would next question correct liner length, insulastors installed properly, etc. that are often overlooked and assumed to be in good condition.

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  Richard Bateman I used to be Technical Director of a welding electrodes manufacturing company producing mig wire like ER 70 S-6 for many years, as experts in welding we found as others have mentioned the following factors could affect stability of arc: 1. Cast 2.Helix 3.Cleanliness of wire (wire drawing lubricants affect the transfer of current) 4. final strenght of wire as left the last drawing die. 5 Copper adherence 6. good wrapping of wire. 7. tolerance between the wire diameter and contact tube (check if you are using wire in inches but by aproximation sometimes people asked for 1,2mm and accept 0,0045"( true equivalent 1,14mm) without change of contact tube. 8. Excesive pressure on feed rolls. 9.Hose torched. 10. cleanliness of contact linersside the hose(torch).

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  Effendi Sitanggang The most issue in production welding that I found is the welder use the contact tube in imperial size but the welding wire in metric.
  This could affect the stability of arc.

  
  

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  Kannayeram Gnanapandithan in manufacturing, Cast and Helix are important for smooth feeding and arc stability along with other issues like over tightening the rollers, groove type in rollers etc
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  • Shankar N only the arc is unstable when there is wire feeding problems in case of MIG welding process the causes for the problem are: contact tip blocked or feed rollers are worned out, and even liner is not cleaned you can face the unstable arc

    
    

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    Michael Spiess Don't forget the issue of to much coating on the welding wire surface. This could be the reason for clogging the wire in the liner as well. Further could be the welding wire surface full of little fines, which has also the reason to clogging the wire in the liner.
    Anyhow, the result is a lot of rework and gives you the reason to looking for a new welding wire manufacturer.

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    Ross Barnes To assist in eliminating clogging due to wire residue you can purchase wire cleaners which are clamped onto the wire just before they enter the feed rollers.