heat insulated, cold insulated

[picasa]

A pipe can be heat insulated, or cold insulated. What is the difference? Without the low thermal conductivity of insulating material, what else is going on?

 

[SnTMan]

I wouldn't use styrofoam for heat insulation.

Regards,

Mike

 

[arto]

here's a couple that come to mind:
cold pipes will sweat [condense air moisture] & the insulation can get wet.

the insulation can melt or thermal crack .

for Stainless, get low leachable chloride insulation per ASTM C795

 

[NozzleTwister]

Expanding upon what arto said about cold pipes sweating.

Cold Insulation and its installation techniques are designed to prevent sweating by not allowing air to get to the pipe (the insulated portion).

Cellular glass is typically used as insulation on cold lines because of its extremely low permeability. Also all cracks and seams between insulation pieces and the insulation and pipe are sealed to prevent moist air from getting to the pipe. Then the insulation is covered with a moisture barrier and an aluminum jacket.

Hot insulation is very permeable and counts on the heat of the pipe to drive out the moisture. Common materials are Calcium Silicate, Fiberglass and Mineral wool. They should not be used where the pipe might operate below the ambient due point.

Search around a little on the net and you should find a lot of info.


NozzleTwister
Houston, Texas