Aerogel Boiler Insulation.

Not sure where to put this thread so if it's in the wrong place, I apologise in advance.

If you aren't aware of aerogel here's the wikipedia entry; http://en.wikipedia.org/wiki/Aerogel.

It holds many entries in the guiness book of records for its insulating properties.

I am planning on using aerogel to insulate my 7.25 gauge locomotive.

I was wondering if anyone has any experience in using aerogel insulation on a steam loco (in any size) and what the results were. On the face of it, it should be a great material to use, but I have no idea if it's been tried, and to what success.

 

If it is as fragile as I suspect, it would be useless in the rough and tumble of a loco shed.

 

Thanks for the reply. Maybe I should have been more specific. I will be using an aerogel blanket, which is an aerogel composite, which claims to be "tough and durable".

http://www.buyaerogel.com/product-category/blankets/

 

Probably fine for your loco, but could be seriously expensive for full size. Also the normal gap is in excess of 25mm, so it isn't really bulky enough to be constrained in the cladding.

 

Using in conjunction with another cladding material would solve the bulk issue, or perhaps just usng it around the Firebox area( the bit you least want to rapidly cool down, Cylinder cladding perhaps the ideal application ?

 

Ceramic blanket from heritage steam supplies is £1.30 per sq ft for 25 - 50mm thick rolls. The thickest (10mm) aerogel blanket is about £3.40 (equiv) in the USA, which would need transport and import tax on top. Perhaps someone should buy some for a loco and do tests on cladding temperatures, so as to see how much heat is saved - then convert to coal burned and hence cost of running the loco.

Over to you

 

The other concern is permeability that insulating layers that dont ' breathe' prevent water from leaks and condensation from standing cold dissapating resulting in excessive rusting....

 

A fair point which leads to a question...

Whenever I see a boiler come out of the works, its almost always painted on the outside, I assume this is to help prevent rusting. If rust is such an issue, why is this paint not reapplied every year, it seems a few pots of heat proof paint would be far cheaper than having boiler work done.

 

It does help prevent corrosion, but only from the outside. Most boiler repairs are due to thermal effects (repeated expansion & contraction) and scouring caused by water flowing at a mad pace in confined spaces on the inside. Sadly a coat of paint (or ten) won't prevent broken stays or a grooved firebox.

Also...

To do a thorough job you'd have to take the boiler off, de-lag it & relieve it of all that plumbing in the cab, which is a major undertaking - especially on a tank loco;
Most railways hire in a socking great road crane to do boiler lifts, which costs a bit;
Getting the cladding sheets off almost invariably makes a righteous mess of the finish paintwork so that'd have to be dealt with too.

I'd suspect that most external corrosion damage comes from standing around between overhauls with the insulation still fitted. It'll tend to absorb moisture from the air & that'll just sit there and cause wrongness to happen.

P.

 

Guitar, Regardless of the above if you do use the aerogel, please feed back to the forum how it performs.