Gas over flux coated wire

[Harvey the bad boy]

Hello everyone a quick question has anyone tried a whiff of CO2 through the torch when using flux cored wire? I wonder if is produces good results without using vast ammounts of CO2, I do realise it would not tbe the cheepest welding but it might produce some worthwhile results.

 

[pedrobedro]

There used to be a fluxed wire for use with co2, I don't know if it is still available.

 

[TechnicAl]

If you use a gas shield with wire designed to be gasless you run the risk of embrittlement. Gasless wire is designed to accept the ingress of the atmosphere yet remain ductile, in other words it needs the air. If you exclude the air by shielding you will prevent certain reactions from taking place and this could cause problems.

Most Hard Surfacing wires depend on the atmpospheric ingress for their properties so you should never use shielding gas unless the product data sheet allows it

If your welds are purely cosmetic using a gas shield can improve the bead appearance (and it can make it worse) but all I have ever tried is Argon rich gas and it depends on the welding position and the parameters used.

 

[pedrobedro]

Here it is. It looks like specialised stuff for pressure vessel and ship building. I thought I hadn't dreamt it.

 

[TechnicAl]

Here it is. It looks like specialised stuff for pressure vessel and ship building. I thought I hadn't dreamt it.

They are Gas Shielded flux cored wires as opposed to the Self Shielded (Gasless) flux cored wires usually talked about on here. The gas shielded varieties usually run DC+ like solid wire whilst the gasless usually run DC- which is why you need a set that is polarity changeable.

They are 2 distinct different processes.

There are a lot more grades of gas shielded than gasless. Gasless is just about restricted to mild steel and hardfacing whilst gas shielded even includes stainless and fancy nickel alloys.

 

[runnach]

Reasonable description here on dual shield>

http://en.wikipedia.org/wiki/Flux-cored_arc_welding

I've only used dual shield once on 316L SS.