RateBeer

Metallurgy Question

read 525 times • 8 replies •

Thread Frozen
 
bitbucket
beers 2160 º places 63 º 22:09 Sat 2/9/2013

My current brewery setup has a lot of soft connections (AKA silicone tubing). Iím looking at converting most of it to hard pipe connections. I have three stainless ball valves, and would be using stainless quick disconnects around the pump, etc.

How well does stainless get along with copper in the beer-producing scenario? Do need to worry about reactions on threaded connections? With dissimilar metals in contact, I worry that I could be creating a short-circuit reaction of electrolytic corrosion.

But the googles arenít giving me anything definitive. I always use a union when going from between galvanized and copper, but not sure whatís up here. Adding eight or more unions to the mix would be annoying.

I could also go with CPVC, and itís cheaper.

Any advice?

 
erway
beers 1004 º places 41 º 22:15 Sat 2/9/2013

Schedule 80 and CPVC would become brittle at some point. Copper works fine, but the problem is with getting all those closed systems clean without ever using caustic. Buy a bunch of PBW and run a cleaning cycle of 30 minutes at 155 after every brew. Run a phosphoric acid cycle (Acid #3 or even 5) every 12th brew or so to make sure you are keeping an untarnished and sanitary finish on the copper.

 
bitbucket
beers 2160 º places 63 º 10:20 Sun 2/10/2013

Thanks!
I need to find a local source for food-grade acid.

 
StefanSD
beers 2218 º places 45 º 10:25 Sun 2/10/2013

Originally posted by erway
Schedule 80 and CPVC would become brittle at some point. Copper works fine, but the problem is with getting all those closed systems clean without ever using caustic. Buy a bunch of PBW and run a cleaning cycle of 30 minutes at 155 after every brew. Run a phosphoric acid cycle (Acid #3 or even 5) every 12th brew or so to make sure you are keeping an untarnished and sanitary finish on the copper.

why not Schedule 40 pvc?

 
SpringsLicker
premium
beers 3253 º places 139 º 11:35 Sun 2/10/2013

Originally posted by bitbucket
Thanks!
I need to find a local source for food-grade acid.


This is what I use

You might have these guys near you

 
erway
beers 1004 º places 41 º 15:22 Sun 2/10/2013

Originally posted by StefanSD
Originally posted by erway
Schedule 80 and CPVC would become brittle at some point. Copper works fine, but the problem is with getting all those closed systems clean without ever using caustic. Buy a bunch of PBW and run a cleaning cycle of 30 minutes at 155 after every brew. Run a phosphoric acid cycle (Acid #3 or even 5) every 12th brew or so to make sure you are keeping an untarnished and sanitary finish on the copper.

why not Schedule 40 pvc?


Boiling temperatures will eventually cause cracking in schedule 40. Add on to that the need to run alkaline and acidic cleaning cycles and you have a pretty sure fire way to get serious cracking in a fairly short amount of time.

 
bitbucket
beers 2160 º places 63 º 17:11 Sun 2/10/2013

Originally posted by erway
Originally posted by StefanSD
Originally posted by erway
Schedule 80 and CPVC would become brittle at some point. Copper works fine, but the problem is with getting all those closed systems clean without ever using caustic. Buy a bunch of PBW and run a cleaning cycle of 30 minutes at 155 after every brew. Run a phosphoric acid cycle (Acid #3 or even 5) every 12th brew or so to make sure you are keeping an untarnished and sanitary finish on the copper.

why not Schedule 40 pvc?


Boiling temperatures will eventually cause cracking in schedule 40. Add on to that the need to run alkaline and acidic cleaning cycles and you have a pretty sure fire way to get serious cracking in a fairly short amount of time.

Yes.

Schedule 40 PVC pipe - (Polyvinyl Chloride) has a rated maximum usable temperature 140F (60C)
Schedule 80 CPVC - (Chlorinated Polyvinyl Chloride) is designed for water up to approx. 180F (82C)

So neither is designed to handle boiling temps, but CPVC comes 40 degrees closer. Home brewing pumps never put enough pressure on the pipe to cause a problem, so youíll probably never see a burst pipe, but there are other problems.

 
Quasimodo
beers 217 º 17:48 Sun 2/10/2013

Iím not a metallurgist, despite achieving a 4.0 in advanced metallurgy many years ago. However, the only thing potentially useful I can tell you is I use copper connected to stainless in the BK and my beer doesnít taste weird because of it. Your mileage may vary.

I also use copper and stainless connected to plastic in the secondary with no detectable off flavors.

 
erway
beers 1004 º places 41 º 06:46 Mon 2/11/2013

Originally posted by Quasimodo
Iím not a metallurgist, despite achieving a 4.0 in advanced metallurgy many years ago. However, the only thing potentially useful I can tell you is I use copper connected to stainless in the BK and my beer doesnít taste weird because of it. Your mileage may vary.

I also use copper and stainless connected to plastic in the secondary with no detectable off flavors.


The issue isnít really off-flavors per se. With copper, you could actually increase yeast growth during the lag phase through increased zinc levels (though you may need to cut back or eliminate yeast nutrients to avoid using a toxic level (for the yeast that is) of zinc). The issue is how long you can use those plastics without them breaking/cracking.

Homebrew Shops - A collection of homebrew shops and supply houses submitted by RateBeer readers

Homebrewing Articles - RateBeer Magazine's homebrewing department

Homebrew Recipes - Experiment, share and post your own homebrew recipes

Until we can make beer come out of your monitor...

Beer2Buds
Send Beer Over The Net

Free signup now. Even out a trade, keep good vibes alive, say hi with a beer