Dry pipe system and nitrogen

[cdafd]

dry pipe systems and nitrogen

What pros or cons have you seen trying to use a nitrogen system in a dry pipe system.

 

[PEDARRIN2]

One pro is reduced (none) oxygen so there is reduced potential for corrosion.

One con is increased cost for equipment (usually requires air compressor with the nitrogen "generator).

 

[chicopee]

You could set up a bank of high pressure nitrogen cylinders with a regulator feeding the dry pipe system but what is the reason for doing it when historically air compressors are used?

 

[cdafd]

So I read nitrogen helps does not help,,,


May extend a system life two years???


Seems also a continued maintence problem, and someone has to know how to maintain it???

 

[chicopee]

Continued maintenance problem in what aspect? N2 gas is inert, therefore the rubber seal on the dry sprinkler valve clapper should be compatible and maintain its integrity. Also, while there is a very small amount of air leakage controlled by an air compressor, a bank of high pressure N2 cylinders should last a very long time and in my opinion would be relatively maintenance free.

 

[cdafd]

The system proposed uses a nitrogen generator and a storage tank.

Generator woukd replinish the storage tank when it got low.

 

[MGXFP]

What I typically see is nitrogen generators in small cabinets. Since N2 is 78% of the atmosphere these generators have a membrane that filters out the rest of the stuff leaving N2 gas.

I'm not sure how a N2 rich environment wouldn't greatly reduce corrosion. Removing O2 can only help. Potter has a presentation online showing their results.

http://www.pottersignal.com/nitrogen/

 

[cdafd]

Newton

I saw the report, and that was helpful

 

[MGXFP]

Also diatomic gas [N2] is less susceptible to pressure variances due to temperature changes than atmospheric air.

 

[RiskConslt]

It seems that we are finally settling on a solution to MIC, pipe scale, and corrosion in all forms: nitrogen charging, even in wet pipe systems. It makes too much sense and has some good track record so far. Look at NACE for more information on long term tests with black iron vs. galvanized vs. nitrogen charged. A reasonable system I have seen is N2-Blast:

http://www.southteksystems.com/n2-blast.asp.

(I am not a salesman) the approach of a generator and tank creates the simplest solution.