Jeff Normand is correct in terms of the 1st exposed thread at the fitting having less depth of material than a schedule 10 roll groove, however most corrosion we see is related to oxidation as opposed to MIC. The problem with roll grooves tends to be water trapped between the grooves sitting in the “damned” area regardless of pitch of pipe or the rating of the gasket used with the coupling (in dry pipe or reaction systems).
Bob Caputo > On Jan 20, 2021, at 1:07 PM, Jeff Normand via Sprinklerforum > <[email protected]> wrote: > > I have been designing with sch 7 pipe for over 25 years. Not sure about > longevity. But you mentioned A53 unlisted pipe. Possibly getting listed? > > I would really like to see comparisons of sch 7, 10 and 40 for corrosion > and MIC. Specially treated pipe some manufacturers claim. Always heard that > sch 40 threads are just as bad as sch 10 grooved. > > Jeff > > On Wed, Jan 20, 2021 at 12:45 PM Scott Futrell via Sprinklerforum < > [email protected]> wrote: > >> Considering how much corrosion I've observed and documented in wet and dry >> systems in schedule 10 in 8-15 years - not MIC - we only specify schedule >> 40. >> >> Scott >> >> Office: (763) 425-1001 x 2 >> Cell: (612) 759-5556 >> >> -----Original Message----- >> From: Sprinklerforum <[email protected]> On >> Behalf Of Steve Leyton via Sprinklerforum >> Sent: Wednesday, January 20, 2021 11:07 AM >> To: [email protected] >> Cc: Steve Leyton <[email protected]>; Matt Grise < >> [email protected]> >> Subject: RE: schedule 7 pipe? >> >> Considering how much "Sch. 7" we've seen perforated by MIC, and also that >> our firm is heavily invested in the institutional and educations sectors >> where clients want 50+ year buildings, we only spec' Sch. 10 and 40. >> >> Steve L. >> >> -----Original Message----- >> From: Sprinklerforum [mailto: >> [email protected]] On Behalf Of Matt Grise >> via Sprinklerforum >> Sent: Wednesday, January 20, 2021 7:58 AM >> To: [email protected] >> Cc: Matt Grise <[email protected]> >> Subject: schedule 7 pipe? >> >> Has there been any push/interest in allowing unlisted (standard ASTM A53) >> schedule 7 steel pipe to be allowed by code in place of the listed "flow" >> piping options? >> >> Matt >> >> _______________________________________________ >> Sprinklerforum mailing list >> [email protected] >> >> http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org >> _______________________________________________ >> Sprinklerforum mailing list >> [email protected] >> >> http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org >> _______________________________________________ >> Sprinklerforum mailing list >> [email protected] >> >> http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org >> > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
