Building a brewery from stainless, questions about back purging

[Kahl]

Hi Guys,

First post here and I'm pretty new to TIG welding (built my cart and that's all ). I'm about to start piecing together parts to build a brewery. It will involve a bit of stainless welding and it sounds like I should be back purging my welds to maintain cleanliness and corrosion resistance.

Does this HAVE to be done with Argon?? or can I use the shielding gas from my MIG (co2) for this purpose??? I'm just thinking it might be a little easier for me to setup and control that way, not to mention co2 is a lot cheaper

Thanks in advance,
Karl

 

[Brad93]

It needs to be argon. In some circumstances you can use Nitrogen iirc. but argon is best

 

[Kahl]

Cool thanks

 

[Richard.]

Yes you need to be protecting the back side but it doesn't always need to be done with a purge. It depends on the joint type and how easy it is to get to it but something as simple as a tight fitting chill block on the back can suffice to eliminate underside oxidising/sugaring/coking.
If a purge is the only way it needs to be argon and you need to of filled the volume of the part a number of times over before starting to weld and reducing your purge flow rate.
Seal any gaps and put a vent in it for the air to be pushed out.

 

[ronan]

Don't have the argon at too high a pressure either as it pushes the weld pool outwards, leaving an odd profile inside the pipe.

 

[Aesgarth]

Any specific items you plan on making? I've been looking at the idea of making myself a conical fermenter out of stainless, just a small (somewhere between 20 and 50 gallon) for my own use, but I'm not entirely sure how to go about making the cone part.

 

[roofman]

Brewdexter is the man to speak to over this brewing game

 

[Brad93]

H

Any specific items you plan on making? I've been looking at the idea of making myself a conical fermenter out of stainless, just a small (somewhere between 20 and 50 gallon) for my own use, but I'm not entirely sure how to go about making the cone part.

Have it laser cut & rolled. Can put you in touch with a company who could put it as part of their next order. Based in Essex thioigh.