Opinions wanted! I have a chance to pick up for free some 2.5"-3"x1/8" wall thickness Aluminum pipe. I have read on D.O.W. that woodgas will corrode the Aluminum. My question is, how long will Aluminum pipe at this thickness last in hours of run time on a stationary generator and could the interior be coated with paint or something else in the form of a thin liquid that would hold up with woodgas? I use exhaust pipe now for cooler, but would like to make out of Aluminum because of it’s superior heat transfer. If not, I guess I will make it out of stainless. If anyone has experience with this, your imput would be helpful. Dan
If you could find a coating that would adhere to the aluminum and coat the inside? Yeah aluminum has a unique property as it will try to dissipate heat faster than it can absorb it. If you could find a coating that would stick to it maybe get it powder coated or something this would be the way to go.
Danny, Hard call. I have had aluminum products hold up well and have had steel products hold up well BUT I have had both aluminum and steel stuff rot through in a hurry. I think it depends on how pure the metal is. If there is a lot of variation in the composition then galvanic corrosion will take place between the different areas. The “vinegar” formed in the woodgas process is probably the biggest culprit. I tend to leave my systems open after full shut down so the internals can dry out. Moisture left condensing throughout the system is a recipe for disaster. I also paint things black and leave them in the sun. Good luck with paint. It will eventually peel or crack and then the galvanic corrosion I mentioned will take place. Regards, Mike LaRosa
I thinking that powder coating the aluminum will pretty much kill its ability to efficiently transfer heat.
Hi Mat, Mike and Richard; Thanks for the replies guys. It appears that aluminum might not be suitable. Guess I will go to stainless when it comes time to replace current cooler. Dan