dry pipe galvanized vs steel pipe

[cda]

any opinon if galvanized is any better than steel in a dryp pipe system???

http://ecscorrosion.com/galvanized-steel-piping/

http://ecscorrosion.com/wp-content/uploads/2013/09/White-Paper-Six-Reasons-Why-Galvanized-Steel-Piping-Should-NOT-be-Used-in-Dry-and-Preaction-Fire-Sprinkler-Systems.pdf

 

[FM William Burns]

A little late to the game but we are seeing galvanized piping being replaced in attics here in the north on dry systems and in pool/boiler rooms too. It will hold up better in corrosive atmospheres externally but I do agree with the report were as they are both subject to corrosion. Just recommended some for a couple risers in a Hotel's pool equipment room since the black pipe is the worse I've seen in 30 years.

 

[Frank]

There is a mixed opinion on that. Conventional wisdom is that galvanized is better. However that is somewhat contraindicated by newer research and experince that has shown that the galvanizing can focus MIC or other corrosion pitting causing earlier failure than for black pipe that typically has uniform corosion rates in partially filled systems with air as the pressurizing/supervising gas. We have seen Galvanized preaction fail in under 10 years in a preaction system. the galvanizing can focus MIC causing earlier failure than for black pipe in partially filled systems with air as the pressurizing/supervising gas. 98% nitrogen filling will help prevent corrosion.

http://www.southteksystems.com/pdf/Technical-Report-Corrosion-Part-2.pdf

 

[FM William Burns]

I concur and can't argue that Frank.........the replacements we are seeing are for very problematic conditions and it's basically a Catch 22 situation where we are seeing replacements. We have not had any replacement experiences beyond five years.......we are requiring internal inspection at fire year intervals on all system piping finally.

 

[fireguy]

Fire Protection Magazine Jan 2014 has several articles about corrosion.

Fire Protection Magazine

550 High Street, Suite 220

'Auburn CA 95603