Scott: I don't know if this was already addressed - but to your point about zinc coated pipe. We specify it over schedule 40, at least in dry-pipe systems, because it performs better than schedule 40. Yes, galvanized piping will corrode eventually; but not nearly as fast as black pipe (in a dry system). But maybe as importantly, the level of scale build-up will be considerably smaller. The more scale build-up, the more opportunity for scale to dislodge during system activation and obstruct flowing sprinklers. FM still prefers galvanized steel to black on dry and preaction systems, though they'll accept black steel when the system 'air' pressure is maintained with an inert gas. THAT may be the ideal solution, if you can get the owner to spend the money on an inert gas system.
Mark A. Sornsin, PE| Fire Protection Engineer Ulteig Engineers, Inc.| Fargo, ND [email protected] ------------------------------------------------------ galvanized pipe: not accepted in Mist Systems by FM for the very reason that one can not guarantee the plating has integrity across the entirety of a twenty-one foot stick. which begs the question, why are we specifying zinc plated pipe and not home-rule, old-school Sch 40 black-steel? Scot Deal Excelsior Fire Protection _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
