Dual Shield wire

[northwest]

Been hearing quite a bit about this lately, one guy I know has been really investigating it as he claims it is big in Europe and there are no real inspectors set up in the UK, I cannot see this myself but I would be very interested in hearing from anyone that actually knows.
I understand Dual Shield to mean flux cored alongside a shielding gas.

 

[Jelly_Sheffield]

Dual-shield is a trade name for particular brand of FCAW-G (Flux-Core Arc Welding - Gas Shielded) wires.

There's a long thread from about 4 years ago here that gives a little bit of useful background.

My understanding has always been that the big advantage of FCAW-G is that if you select a wire with a fast-freezing flux, it's possible to run positional welds at much higher power levels (and thus deposition rates) than conventional short-circuit MIG...

For that reason it tends [IME] to be used to custom WPS's in workshop-based heavy fabrication applications to increase productivity, often paired with running Metal-Core Wire for all the weldments that can be run in flat position or with a semi-automatic welder.

Other people with a broader wealth of welding experience can probably illuminate the specific pros and cons better.

 

[northwest]

There's a long thread from about 4 years ago here that gives a little bit of useful background.

Very interesting and as I expected @Brad93 gave some useful insights. I was not unsurprised to see the OP was from Portugal as my information was from Europe. I thinjk it is an interesting concept but as with everything it;'s rate of uptake will be dependent on cost, overall and saving.

 

[Jelly_Sheffield]

In my (very limited) hands on experience with it, it's somewhat unforgiving compared to both MIG or Arc Welding...

Running fast with slag means small errors can rapidly result in big faults that need to be back-gouged well into the parent metal to verify there's no slag.

However I took away the impression that once you got your hand in, it would be a very nifty trick to have up your sleeve...

If I ever get my biggest MIG hooked up again I would be tempted to gamble on getting a 5kg spool of 1.2mm Dual-shield and spending the time really practicing with it, not having much space or lifting equipment it potentially suits my needs when working on larger things.

I thinjk it is an interesting concept but as with everything it;'s rate of uptake will be dependent on cost, overall and saving.

In the UK I have seen it used by a Wood Group run subcon fab shop inside a client site, and by two of our subcontractors (one a multinational and one central-belt based but with an enviable client list).

Specifically for welds where running FCAW-G uphill on thick sections, saved either:
• time and money doing rigging, or
• space
over manipulating the parts so it could be welded in flat position.

That fits your expectations perfectly, sophisticated operators doing high volumes of work, who have the time and manpower to work out how to utilise the technology in a cost effective way, deploying it to save money.

I was not unsurprised to see the OP was from Portugal as my information was from Europe

I have a portuguese business partner who project-manages quite a bit of heavy fab work done locally to him, so I will ask about how much they use it when we meet in the new year...

Although most of what we work on together is 316 stainless equipment framed in Corten skids, which might colour the response.

In any case it never does any harm to remind people at work I'm not just a money man, and do actually like to get my hands dirty.

 

[Brad93]

Love a bit of dual shield.

Problem is a lot of people running it like it's a self shielding wire. Outdoors in a breeze "oh it's alright it's dual shield, it'll be fine"

It's just as susceptible to nitrogen embrittlement and internal porosity than solid wire.

Thats before you contend with moisture in the wire, worm tracks and general lack of penetration.

Like MMA welding it lends itself to good fusion, but it will never been as deeply penetrating to the root of a fillet as solid wire.

Vertical, overhead, horizontal etc it's going to **** all over the productivity of normal MAG welding.

The other benefit, due to the powder flux/metal in the core, is the fantastic mechanical properties it can achieve.

 

[zzr1200]

I believe a 15kg roll of dual-shield is about £100, a 15kg roll of solid wire is about £30.00, I'd love to try dual-shield but not at 3 x the price of standard solid wire.

 

[Erie Fred]

I believe a 15kg roll of dual-shield is about £100, a 15kg roll of solid wire is about £30.00, I'd love to try dual-shield but not at 3 x the price of standard solid wire.

True, however, if you have the need for it, it works very well.

I tried some 777 or "triple seven" all position flux core, weld lab showed me how to run uphill with it, very nice.

As above, when it runs badly, it goes south real fast. Wagon tracks & major swiss cheese porosity, needing air arc to remove.

 

[Munkul]

As above, when it runs badly, it goes south real fast. Wagon tracks & major swiss cheese porosity, needing air arc to remove.

I think this is one of the main reasons why we brits never really got into it. It's quite finnicky.
It doesn't do well sitting around and takes moisture in meaning the whole reel has to be scrapped if its sat for a year or two in the cold and damp.
I've tried a few different dual shields, they run awesome when they run good, but getting rid of wormhole porosity when it gets old... just impossible.
Its the most frustrating thing... you lay what looks and feels like a beautiful weld, then you peel the slag off and it looks like swiss cheese

If you're regularly using 15kg+ a month on out-of-position work then I think it makes loads of sense. I am always surprised that more plant repair people don't use it.

 

[Erie Fred]

I think this is one of the main reasons why we brits never really got into it. It's quite finnicky.
It doesn't do well sitting around and takes moisture in meaning the whole reel has to be scrapped if its sat for a year or two in the cold and damp.
I've tried a few different dual shields, they run awesome when they run good, but getting rid of wormhole porosity when it gets old... just impossible.
Its the most frustrating thing... you lay what looks and feels like a beautiful weld, then you peel the slag off and it looks like swiss cheese

....and it really piles it up too.....man can it pile up metal.

 

[zeppelin builder]

it almost killed stick welding for heavy fabrication and the rutile based wires leave a great finish , wire is best stored in a temp controlled store , id say about 3 times faster than stick !
backing tiles can cope with massive gaps and bad fitting , beware of stick tacks on vert fillets
(platers revenge )
oerlikon , nittetsu, bohler all good stuff
voltage for 1.2 start around 24 volts and dial wire in to suit , when capping leave it a bit under flush it likes to sit in a hollow a worn grinding disc between passes can be used when on the climb say 7 o clock on a pipe knock the wire speed back a bit and it wont build up too much
i have mine on a miller xmt and suitcase using air liquide 1.2 wire and ar 20 co2 i bought some 5kg reels vac packs
probably ex pipeline stuff and it always amazes me the soft quiet crackle