Sanitary welds

[timboss]

Hi Gents

I'm getting close to having my keg welded up, as mentioned in another thread here it is recommended that back of TIG welds be back purged with argon to prevent sugaring. This is sanitary and stops corrosion?

So I did some research, and this method is popular with the beer boys, which is well and good as they cut the entire top off their kegs off so it's easy to get access to the back of the weld, but this wouldn't exactly be possible with our kegs as far as I can see, and I'm sure just sticking a line in your keg from your argon tank and turning that shit on willy nilly is going to do anything that is classified as a back purge.

But that said, I'm now paranoid over all the sanitary and corrosion threats being made if the back of the welds aren't protected.

So whats the experience of people here? There seems to be plenty of guys here with TIG and Stick welded kegs, are your boilers plagued with corrosion and bacteria because your welds were not back purged? Or is this all just hype?

[karrotbear]

Hey timboss,

I had mine welded professionally (apparently) and they didn't back purge so I definitely ended up with sugaring on all of my welds (inside of the fittings and on the join to the keg). At first I was pretty annoyed (seeing as I waited 3 weeks for these), but then I thought fuckit I'll just go get some SS wire wheels and get rid of the rust (it had already started rusting within the first day). I went back to the welder and asked for some pickling paste, and just scrubbed out the rust using the wire wheels. Then just applied some pickling gel to the inside and outside of the weld and left it for about 45min. Washed it off and now I'm sitting pretty.

If you cant find a SS wire wheel in the size you require you can probably use the plain old carbon steel ones, and then after getting rid of the rust redoing it with another wheel (kind of red wires made of some plastic - in the product ordering form it is for removing rust form SS fittings - masters should have them I think). I did that with my other keg and it seems fine now :)

I think the main issue with sugaring is the potential for bacteria to grow there etc etc, but in terms of a boiler - you are raising the temperature well above 60 every time so I doubt it would be an issue for us, where as it would defs be an issue for beer makers.

[aliced]

Garden lime will neutralise the hydrofluoric acid, just keep sprinkling it on till it stops bubbling.

Just a tip :)

[Muppet]

Hi Gents

I'm getting close to having my keg welded up, as mentioned in another thread here it is recommended that back of TIG welds be back purged with argon to prevent sugaring. This is sanitary and stops corrosion?

So I did some research, and this method is popular with the beer boys, which is well and good as they cut the entire top off their kegs off so it's easy to get access to the back of the weld, but this wouldn't exactly be possible with our kegs as far as I can see, and I'm sure just sticking a line in your keg from your argon tank and turning that shit on willy nilly is going to do anything that is classified as a back purge.

But that said, I'm now paranoid over all the sanitary and corrosion threats being made if the back of the welds aren't protected.

So whats the experience of people here? There seems to be plenty of guys here with TIG and Stick welded kegs, are your boilers plagued with corrosion and bacteria because your welds were not back purged? Or is this all just hype?

I'm a pipe fitter/ coded welder, in the industry everything SS coded is back purged. It's as simple as purging the air out and keeping a slow steady flow of argon (to prevent more air entering) as far as for a boiler keg I personally wouldn't but hey if your super fastidious fine do it. Not purging wil get a slight 'cauliflower' effect on the inside of a root run, for something that isn't full penetration it really isn't warranted. If you were fabricating something that you were selling for food service I'd say it would be needed for QA

[newbiboozer]

When I tiged my boiler I tacked all the fittings in place then blocked all the holes up with tin foil tape. I made up a t piece to tap into the argon line with a needle valve to regulate flow and a hose with a fitting stuffed with ss scrubber to act as a defuser I then poked the hose in through the foil. Run it for a couple of minutes then weld away. Worked really well no shitty welds on the inside.

[Sam.]

I have some welds in a couple of boilers that look a bit shit and rusty and I am yet to taste and ill effect :handgestures-thumbupleft:

This ain't beer, your boiling the shit ;-)

[Canadoz]

I have some welds in a couple of boilers that look a bit shit and rusty and I am yet to taste and ill effect :handgestures-thumbupleft:

This ain't beer, your boiling the shit ;-)

Probably good for you, maybe a little iron oxide sneaks through to supplement your dietary needs. :laughing-rolling: