Perlite/Satanite Brick Furnace Lid Trial (by Fire!)

I still like this idea, it just may need an adjustment. Use Bubble alumina instead of perlite. I could not get the math to work with perlite in high temperatures applications.

http://www.ktrefractories.com/Alumina-Bubble.cfm

 

Good thought. Bubble alumina mixed with a binder of Satanite might very well make a lightweight and very tough furnace. That may indeed be the way to go. I had purchased bubble alumina castable (expensive) to use for some components of the furnace. But I had not considered getting the more commonly available and cheaper bubble alumina and adding Satanite as a binder. Anyone know of a source of BA in relatively small quantities at reasonable prices.

Edit: I did find it on Amazon in a 50 pound quantity for about 150 bucks. The package size is a bit more than a cubic foot. So, denser by quite a bit than perlite. And much much more expensive by volume.

Denis

 

That certainly is a very reasonable approach and one I have thought about. If I thought it would be an extremely long-lasting solution, I would do it. But, I am more and more impressed that nothing seems to holdup well in iron service. I do think the segmented lid would hold up better than the original monolithic one I made and it did last for quite a while. Originally, my idea of using perlite/Satanite in 12 segments for the lid was in good measure as a test bed for P/S and segmentation and angle of incline for segmentation. I am pretty sure that a very low incline angle (like 10 deg) puts too much compression on the segments as the lid expands and contracts. I am guessing 20 degrees may be about right.

I am thinking the wool/Satanite will also not be a permanent lid solution. But repair of area failures will be simple, quick, cheap, and incremental. A castable failure is “stop the presses” event that takes me a minimum of 10 days to fix.

So goes the quest for the optimal compromise, anyway.

Denis

 

The alumina bubbles are not as good a insulator as the perlite. I guess that is the price one pays for the temperature rating. KT may also be able to recomend a mortar/binder.