Tank Welds

[BrewsterAles]

Hi,

I recently purchased a couple of 200 gallon used dairy tanks that I am going to have converted to an electric brewhouse. The plans call for (12) 1.5" TC ferrules and (1) 2.5" TC ferrule to be added to the tanks. A local welder who has experience with stainless and a little experience with sanitary welds did a "trial run" by welding an extra ferrule onto one of my 1/2 bbl SS tanks.

What do you think of his work? He admittedly stated he does not have the equipment now to "backflush" for sanitary welds but will get the equipment to do the big job. The weld pictured is without that equipment and process but he states he does feel comfortable doing the sanitary welds once he gets the equipment.

Thoughts? Thank you!

[gitchegumee]

Meh. He needs to safely use pickling paste and perhaps a polishing bob to brighten those surfaces. The interior is most important and will likely crust up with "sugar" from oxidized metal if a purge gas isn't used. That leads to pinholes and corrosion sites. Also doesn't look like the inside of the tank has been fused--did he only weld from the outside? That wouldn't be right. You get what you pay for, and making your own equipment comes with a slow, shallow learning curve. Best of luck!

[TGTimm]

Find and hire a certified sanitary welder. I've been battling this same thing for years now, and I'm sick and tired of polishing the turds left by "can-do" welders.

Backflushing with a noble gas isn't rocket science and doesn't require any extra expensive equipment. It requires training and experience.

That finish is by no means ready for CIP cleaning. No visible scratches are acceptable.You'll have to polish it to blend into the rest of the tank and then passivate with nitric acid.

[Foamtime]

the outside of the weld looks good. hard to tell on the inside, but it doesnt look fused like philip said.

the weld also does need to be either pickled or electrolysis polished with a machine that sanitary welders should have (search weld cleaning system on google). If it isnt, then the brownish, reddish colored metal will start to rust because the extreme heat from the welding compromised the chromium oxide layer. You can make a machine to passivate metal pretty cheap yourself with some carbon fiber tow, a 24v power supply, and some 88 percent phosphoric acid, and the protective equipment needed (gloves, acid gas mask)

[BrewsterAles]

Thanks everyone. I kept looking, largely due to your critique of the 1st welder, and found a sanitary welder who has done work for breweries and food industry and is going to take my project on for a pretty good price. Appreciate the feedback!

[TGTimm]

Congrats! The nearest certified sanitary welder to us is about 8 hours away.