Running copper tubes through stainless steel sheet

[GQT]

Hi guys I was wondering about how to pass copper tubes through stainless steel kettle wall. I am going to install a coil inside the kettle for dual usage as HERMS heat exchange and after boil pre-chiller.
If it was stainless steel tube I'd weld it and that would be it but it is copper. (why copper? - simply because bending thumb-thick copper tube is way easier than doing it to stainless steel tube of the same diameter).

I want it as solid and rigid as possible, so tricks like running a barbed connector through the wall and then connecting the coil to the barb with pieces of silicone hose just don't look exciting to me.

Has anyone been there?

 

[timdillon36]

Silver soder.

 

[GQT]

Silver soder.

I thought that but I was advised to stay away from anything with the word "silver" in it. (aspen stakes OK though )
Because silver has some sort of disinfecting qualities and that might suppress yeast growth.
Might be bull but at that moment it sounded reasonable to me.

Have you personally tried silver-containing connections with beer?

 

[2grit]

What is the actual size of the stainless tubing you describe as "thumb-thick"? Why not weld a piece of stainless tubing to the wall of the kettle and adapt to that piece of stainless with copper.

 

[d3track]

I thought that but I was advised to stay away from anything with the word "silver" in it. (aspen stakes OK though )
Because silver has some sort of disinfecting qualities and that might suppress yeast growth.
Might be bull but at that moment it sounded reasonable to me.

Have you personally tried silver-containing connections with beer?

This is new to me - even John Palmer (a metallurgist by day) talks of using lead-free silver solder.

I solder the nipple to my kettle, my whirlpool arm is soldered, and my chiller is soldered, but those joints aren't in the wort like the other two.

 

[GQT]

actual size of the stainless tubing

Copper tubing, not stainless. Stainless is the kettle.
I live in metric world, but I guess it's something about 1/2 of an inch _inner_ diameter, more or less the thickness of a regular plumbing pipe.

Yes I that might work. Welding short stainless pipe with threaded ends through the wall allowing about half inch on either side to stick out, letting the copper tube through it, and tightening it on both sides of the wall with nuts and o-rings. It will not be rock rigid but surely rigid enough for the purpose.

Was looking for easier/less messy way, if maybe some guys have done that before, and would share.

If nothing easier comes up, I will go this way, thank you for the hint.

 

[GQT]

John Palmer (a metallurgist by day) talks of using lead-free silver solder.

If Palmer says so I'd give it a go. But honestly, if there was a way to avoid anything in doubt, I will.
Just, you know... if anything screws up, I don't want to always think, or damn, maybe I shouldn't've done that.

Anyway, I will perhaps try the way described one or two comments above - but as soon as I have some slurry leftovers, I will make some mock starter and leave it to ferment with a silver ring inside the carboy and see how it goes. Might as well be a beginning of a new line of beers!

 

[cilestiok]

Why not use a bulkhead fitting through the kettle wall and then solder threaded ends on the coil inside the kettle?

 

[cilestiok]

If Palmer says so I'd give it a go. But honestly, if there was a way to avoid anything in doubt, I will.

Just, you know... if anything screws up, I don't want to always think, or damn, maybe I shouldn't've done that.



Anyway, I will perhaps try the way described one or two comments above - but as soon as I have some slurry leftovers, I will make some mock starter and leave it to ferment with a silver ring inside the carboy and see how it goes. Might as well be a beginning of a new line of beers!

I have silver solder on plenty of joints in my equipment and never had any issues because of it.

 

[Bellybuster]

Full coupling welded or soldered and compression fitting for the tubing. Look at any Hermes system on here and you'll see it done thousands of times

 

[GilaMinumBeer]

I think you are confusing colloidal silver as a yeast suppressant (Candida Albicans) with just silver in general.

 

[GQT]

I think you are confusing colloidal silver as a yeast suppressant (Candida Albicans) with just silver in general.

True. Never thought silver had to be in exactly this form to become a suppressant. Thought it'd be safer to just stay away. Thanks, it is worth noting for future.

 

[2grit]

Copper tubing, not stainless. Stainless is the kettle.
I live in metric world, but I guess it's something about 1/2 of an inch _inner_ diameter, more or less the thickness of a regular plumbing pipe.

Yes I that might work. Welding short stainless pipe with threaded ends through the wall allowing about half inch on either side to stick out, letting the copper tube through it, and tightening it on both sides of the wall with nuts and o-rings. It will not be rock rigid but surely rigid enough for the purpose.

Was looking for easier/less messy way, if maybe some guys have done that before, and would share.

If nothing easier comes up, I will go this way, thank you for the hint.

You said "stainless steel tube of the same diameter" and I get exactly what you're trying to do here. I wouldn't pass copper tubing through the stainless welded tube. I would adapt directly to the stainless tube with an adapter that fits the copper tubing. If you did it with compression fittings it would be rock solid. IMO, I've welded a thousand fittings in this manner plus I've silver soldered stainless and welding is WAY less messy. It should be done with TIG welding. It would be bullet proof. To be perfectly clear, you would TIG weld a short piece of stainless tubing through the wall of your kettle. Blank ends, no threads. Use compression fittings on the stainless tubing that adapt to your copper. Completely sealed, solid and removable. Hope this helps

 

[brrman]

Silver has anti-microbial properties just like copper.