Foam Glass Insulation 1

[Luk]

Hi All!

Has anyone used foamglass insulation for process piping & vessels?
Any thoughts or comment on this cellular type of insulation?

Thanks!
Luk

 

[unclesyd]

We used it on S/S vessels to mitigate Chloride induced SCC prior to the availability of low chloride expanded calcium silicate insulation. We had a time maintaining the weather coating as it was glass fabric and mastic. The availability of S/S weather coating helped immensely in this respect. We used it around an acid process (HNO3) that if it got on the Foamglas it created H2SO4. H2SO4 in combination with the HNO3 made a very good S/S dissolving solution. It was pretty aggressive on thin wall tanks. We eventually removed it due from all but the distillation columns due to process changes.
The insulators didn’t like to work with it. We found that some people were quite sensitive to H2S, the foaming agent.

 

[stanier]

I have used foamglass on hot oil installations. cellular structure prevents the expansion of hot oil, increased surface area and spontaneous combustion.

No one procrastinated their way to the top

 

[Luk]

Thanks unclesyd and stanier for the insights.

 

[bngreene]

Cellular glass or Foamglas is commonly used to insulate vessels and piping when there would otherwise be concern about the accumulation of moisture or flammable chemicals in an insulation that absorbs and retains moisture, e.g. fiberglass. It is often used when the operating temperature is below ambient.

Its main disadvantage is its cost, both material and labor. It can also deteriorate over time and lose its insulating value.

One alternative to cellular glass is perlite insulation. Perlite is an inorganic silicate or combination of silicates. It is quite good in protecting against corrosion under insulation, but I am not at all sure that it should be used where nitric acid leakage is a concern.

Perlite is often more fragile than celllular glass, but is generaly adequate for applications where there is minimal traffic and where accumulation of moisture is the major concern. It is less expensive than the cellular glass, but probably more expensive than your other alternatives.

I hope this is helpful.

 

[Luk]

Thanks bngreene.
I will check perlite out.

 

[1969grad]

Agree with bngreene.

I use foam glass insulation for below ambient operating temperatures in the pipe or outdoor piping applications as opposed to calicum silicate where there is ambient moisture absorption concerns. The decision is generally based on if the pipe operating temperature is hot enough to drive the moisture out (partial vapor pressure).

Foam glass insulation is nasty stuff to install and the installation cost reflects that fact.

If you do install calicum silicate outdoors you should consider coating the insulation under the sheet metal covering with a mastic. Choice depends on the above.

In selection of any insulation you need to check the hot operating temperature limits of the insulation.

 

[onuigbo]

We are currently using foam glass to insulate our steam distribution lines at 300 degrees F and higher. Although expensive, it has proved very reliable.

We deliver steam as if your life depends on it.

 

[jalvarez]

As it was already mentioned, foamglass is expensive. So the use is normally limited to specific cases.
In double wall tanks cryogenic applications, it is commmon to use it as the insulatio material in the floor, between the two tanks (Good mechanical properties for this use).
The space between the walls is normally filled with in situ thermically expanded perlite, which is also mentioned here.
You asked for vessels insulation. For cryogenic piping, the election is usually ($$$) expanded (in situ or preshaped) polyurethane.
This is all for cryo applications, what's your case?
Have a safe day
J.Alvarez