Microporous insulation
Nanoporous silica board — the one class of rigid furnace insulation that conducts less heat than the air trapped inside ceramic fibre.
1 line · stocked in Ahmedabad
The lines
A different mechanism, not a better fibre
Ceramic fibre, calcium silicate and insulating brick all slow heat with air held in pores tens to hundreds of microns across, and none of them can conduct less than that air. Microporous insulation compacts fumed silica until its pores are below 100 nanometres — smaller than the distance an air molecule travels between collisions. The air stops carrying heat, an infrared opacifier scatters radiation, and the board ends up below the conductivity of still air.
Where it goes in a lining
It is a back-up layer. Classification temperature is 1000 °C and it has no abrasion or slag resistance, so it sits behind a hot face of brick, fibre or castable, at an interface kept below about 900 °C. There it does the work of roughly four times its thickness of ceramic fibre board — which is either heat kept in on the same shell, or wall thickness handed back to the chamber.
What to send with an enquiry
Hot-face temperature, the existing lining layer by layer, the casing temperature if you have it, operating hours, and whether the furnace runs continuously or in batches. With those we can calculate the interface temperature and the heat loss before recommending a thickness.
Where this is the wrong answer
Hot-face duty, anything above 1000 °C, load-bearing positions, contact with molten metal or slag, persistently wet service — and low-temperature equipment bought on fuel savings alone.
Tell us the duty, not the product code
Operating temperature, atmosphere, what contacts the lining, thermal cycling and the existing lining’s failure history — send those and we will come back with a grade and a reason for it.