Calcium silicate insulation - minimum thickness

[gmorin]

I'm using cal sil insulation on a refinery project. The client's insulation table and a couple vendor websites have indicated that 25mm (1") thick cal sil is available, but some of my colleagues are questioning whether it'd be too fragile. They were concerned it may be tough to work with and may break apart under the lagging.

Most of the usage is on small bore pipes.

Any concerns with availability or durability???

Thanks

 

[unclesyd]

We require a minimum of 2", clam shell, on 1/2" and 3/4" pipe depending on the temperature. 1" and above we use 3", clam shell. We try to stay away from 1' thick material on our built up insulation due the frailability problem with the current Cal Sil product. On one part of our process where all the insulation is built up removable the thickness is determine by need plus nothing less than a 2" section even if it goes over the actual required thickness.

At one time Cal Sil was quite strong as it had Asbestos fiber reinforcement incorporated in the mix. The present material doesn't and looses all it's strength when exposed to heat. Cal Sil insulation will an Al weather covering has a fire rating of zilch. Only a SS weather covering will give the insulation any rating.
There are now some Cal Sil products available with a very low moisture content that do have some strength when exposed to temperature.