Seal Welds - Gasless MIG - Stainless 316

[xxxx_guy]

Hi Guys,

I am a beginner welder. I have been trying to weld up some brewing equipment with a flux cored 316 electrode onto 316 stainless steel with a SIP150 welding machine. My problem is I keep getting leaks.

Firstly is this easier with flux cored electrode, solid wire with shielding gas or tig?

Secondly if I am trying to weld around a pipe/internal hole, should I be trying to do 180 degrees, clean off weld and do remainder, or is there a technique to keep the weld pool at each end of the weld liquid to join weld ends up in one go ( ie. jumping from end to end)?

Thirdly is preheat likely to help increase penetration and joining to existing weld (have access to a butane torch)?

Fourthly, is this likely to be too difficult a problem for a beginner welder (keep getting cracks/discontinuities in the weld, can be seen when ground down, also note others in the forum are suggesting different alternative sealing methods - ie. silicone, brazing, soldering, paint)?

Cheers,

Jono

 

[TechnicAl]

Flux Cored Stainless? with a shielding gas?

 

[500e]

Don't think you quite read it as meant TA.
Still would have thought flux core & brewing not a good mix

 

[rtbcomp]

What he's asking is "Firstly is this easier with flux cored electrode, OR solid wire with shielding gas or tig?" My Italics.

I assume the op means flux-cored wire rather than electrode.

 

[TechnicAl]

Ok right

What I meant was (as far as Im aware) there isnt a gasless stainless flux core that will do thin stuff. Usually the gasless SS is big daimeter wire ie 2.4mm +.
So it has to be solid wire with gas and if its brewing equipment it has to be Argon + 2.5% CO2 (specshield 2.5%CO2)

I wanted to know which wire and which gas had he used already?

 

[xxxx_guy]

It is either 0.8 or 0.9mm flux cored wire (I think it is reasonably new to the market - search 316 welding flux in ebay and you should find a few). Sorry about that meant wire not electrode in my original post.

The brewing equipment is my own (I'm do home brewing as a hobby, do about 20L batches) so not commercial, although try to get as much of the flux off as I can.

 

[backpurge]

The norm for any food and beverage stuff is TIG welded, properly purged. This ensures there are no areas for bacteria and other nasties to get trapped which could cause health or quality issues, I know you said it was for personal use but you don't want to poison yourself

 

[Richard.]

Right on. Food and hygiene stainless doesn't have accepted levels for spatter, excessive cap height and especially not slag traps which Id guess the flux cored wire would be very good at producing all 3. It's a Tig job with the welds finished properly by means of pickle paste, regraining and polishing to ensure a perfectly unhinged flow. As above any residue caught in any corners is not good for your health.