heat riser

[thickstrings]

I have asked this on other forums to no avail.......Does any one think this is viable for a riser? : ceramic fiber board coated with this    www.skylinecomponents.com/In-Stock_Rigidizer.html .....  could be a alternative to the vermiculite board that is fragile?

[matthewwalker]

I have no experience with the rigidizer, but ceramic fiber board and formed ceramic fiber risers both work just great. The fiber board is fairly fragile without the rigidizer, but if you used >1" thickness board it is strong enough to hold it's shape and I feel it would last indefinitely. Rigidizer would for sure be that much better, but I do doubt it's necessary.

Depending on where you are you can also ask any refractory supplier for "riser sleeves." These are formed ceramic fiber risers, usually with rigidizer, and work fantastic. I recently saw a picture of a build in a teepee where they were using these. I've been using them for over a year now and they hold up great, it looks like others are starting to use them as well.

[peterberg]

I do have one such a riser made of formed ceramic fiber and firmed up by a rigidizer. I am able to confirm Donkey's findings, the riser itself can be glowing red hot and still stay in one piece. No mass to speak of, 1" thick and super insulating, what do you want more?

[bernardbon]

Hi,

Joris Poul uses this process, I think. He may be a return of experience?


Bernard

[peterberg]

The riser I am using at the moment is supplied by Joris Pouls. His experience with this product is equally good as far as I am aware of.

[talltuk]

Been thinking on this myself as I recently found a technical insulation supplier in the uk witj a branxh here in norwich. Couple of quick questions. What sort of temps does material have to endure in a batch box burn chamber and heat riser and would a board like this or kaolwool be tough eenouhh for lining the burn chamber. Thanks for all the good work and help guys. Off to get my first barrel sandblasted tomorrow, yay!

[matthewwalker]

Not sure about the Kaowool TT, but the ceramic fiber board holds up fine in the hottest areas. It won't hold up to wood abrasion though, so keep it away from where the fuel is.

[ga2500ev]

Matt,

Where can one get these types of boards? Also what the cost comparison to insulated castable refractory?

ga2500ev

[matthewwalker]

You can find refractory suppliers in every metro area, but you need to dig a bit. Think of mills, refineries, heck, just about any large industrial area will have a myriad of refractory needs, so there's always a supplier close by. Millwright union contacts can be helpful in finding suppliers locally. It's never cost effective to ship this stuff in small amounts so do some digging near your area, you'll find something.

No comparison in terms of insulating properties. I don't know the numbers, but orders of magnitude I'm sure. Durability wise they are equally disparate, so use the right material for the application, by which I mean to say, if it's gonna get hit with fuel, use refractory. If it's just gas path, the ceramic fiber is excellent.

Edit: Oh geez, I totally missed that you said cost. Hmm, hard to say I guess since the refractory is sold by weight which with calculations I do as volume. I don't find the board terribly expensive, but it's all relative. As a starting point, I've sourced the board for around $20/board foot. You can find online calculators for figuring board foot area/thickness.

[pyrophile]

You can find the refractory wool in shops which supply the ceramists (in rather big cities or by internet) : Solargil or Ceradel in France. The wool is about maybe 60 euros/M2.Given for 1260 C. I will use it also for a riser.
solargil Fibre ceramique
www.solargil.com/fr/fibre-ceramique/4009-fibre-ceramique-1260-c-en-50-mm.html"]solargil

[pyrophile]

For the riser, the light bricks can be also used but at 3 euros one brick.
Isolating bricks

[satamax]

Question for Peter.

Peter, what do you use for insulating the heat risers? Superwool? How thick?

I'm on some ideas for prototypes, and i need thin insulation around thoses refractory tubes from Landini, because i wouldn't have much space around the heat riser for the gap.

[fdelam]

for french members, all materials can be found there

[peterberg]

Nov 6, 2013 11:57:30 GMT -8 satamax said:

Peter, what do you use for insulating the heat risers? Superwool? How thick?

I've been using rockwool, vermiculite and super wool. When space is tight use super wool, preferably 1" thick.

[satamax]

Thanks a lot Peter.