Polystyrene vs. polyurethane foam for insulation

[cacofes]

Not sure if this is the right forum but I am looking for any experiences with polystyrene foam as insulation material for piping. Seems like polyurethane is widely used but polystyrene comes at almost half the price and also has a very low heat transfer coefficient. I appreciate anyone sharing some experiences with both materials. Thanks...

 

[BigInch]

Haven't seen styrene used on anything but Igloo containers. It is very soft, easily compressible, easily broken up, leaves bits all over the place, and adsorbs moisture so not likely a good outdoor material.

Only put off until tomorrow what you are willing to die having left undone. - Pablo Picasso

 

[europipe]

The blue very strong polystyrene is used for cold insulation from approx. 0 to -110 deg.C.
Azobe blocks for fixed supports.
Greetings

 

[europipe]

http://glasscellisofab.com/en/polystyrene.html

 

[moltenmetal]

We tend to use foamed rubber instead for cold pipe applications. Unlike polystyrene, it is low flamespread and essentially self-cladding. You do need to protect it from UV if it's going in an intense direct sunlight application- there's a white paint/mastic that does this really well.

http://www.armacell.com/

http://WWW/armacell/INETArmacell.ns...Document&Nav=A3AC14FF3DAE932F8025774E006B7BB0

 

[StoneCold]

One of the major problem on cold systems is water adsorption over time. The insulation gets saturated and you lose the insulating effect. For that reason we use this Trymer Polyisocyanurate.
Then we cover it with a moisture barrier and then tin over the top with bands not screws. We also use the armaflex material, but usually on small piping or really small tanks. The joints are the problem on the armaflex, otherwise I really like that product because install costs are almost nothing, it goes on very fast.


Regards
StoneCold

 

[IRstuff]

Styrofoam is used for a number of insulation applications, including underlayers for aluminum roofing, coffee cups, etc. For mass production, it's probably one of the cheapest insulation materials around, but it's also probably the least durable.

TTFN

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[cacofes]

Thanks for all your replies and links provided. We found the information very helpful.

 

[KENAT]

Moisture absorption is a fairly significant issue as I understand it.

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http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
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[moltenmetal]

We use Armaflex or Rubatex because it goes on fast, is self-cladding, is damage resistant, facilitates repair, and is closed cell, rendering moisture absorption moot. Like anything, it can be installed well or badly, with good or poor detailing at joints etc. But compared to ANY clad product, it's a stroke of pure genius.