fire service pipe insulation 1

[MJeng]

Need to insulate an exposed portion of an 8" fire service that typically does not have flow in a northern climate. What is a suitable type of insulation and to what R value?

 

[BigInch]

You can't insulate a no flow line and expect it to remain above freezing for long. Without heat input from some flow from a warmer part of the line, it will eventually cool off and freeze if the temperature remains cold outside. R values are "resistance" to heat loss. It just slows heat loss down. It doesn't stop it.

OK, what you need is insulation and some heat tracing.

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"Pumping accounts for 20% of the world’s energy used by electric motors and 25-50% of the total electrical energy usage in certain industrial facilities."-DOE statistic (Note: Make that 99% for pipeline companies)

http://virtualpipeline.spaces.live.com/

 

[bimr]

Use 2" thick fiberglass ASTM C547 or C612. Owens Corning ASJ/SSL-II; with

Alum Roll Jacketing (0.16 thickness),

Bands: 1/2" x 0.015 SS,

and furnish and install a self-regulating heating cable suitable for contact with the piping, Raychem BTV-CT or equal with indicating light

 

[gerhardl]

...and/or depending on surrounding conditons (nordic climate can be anything from arctic with permafrost up to some degrees below frezzing point some days a year) dig the pipeline down underground at frost-free depth.

 

[stookeyfpe]

And because this piping is for fire protection service, I would recommend the heat trace cable be connected to a supervisory circuit if the site has a fire alarm system. If the heat tracing fails, it needs to be repaired and fire alarm supervision would make the notification immediately.

 

[hydrae]

Have you looked at a dry type fire line
The entire line is kept drained and filled with compressed air at about 20 psi. A special valve senses the air pressure so if there is demand (fire) the valve will allow the water to enter the pipe. After a use, the lined is drained again and filled with air. A small air compressor is needed to maintain steady air pressure.

There are also antifreeze solutions that can be used, needs to be a potable type, and a RP backflow device installed.
Hydrae