Roland, Did Joe tell you on what basis the Technical Committees accepted the Pipe Schedules?
Here is an excerpt from the follow-up post to the you one you posted (EC stands for European Code, and I was going to say British Standard, call it BS, but thought better): "For the EC schedule with max 4 head line, using 32 ft/sec as the cut-off and 130 ft2 spacing I got an average density of 0.192 GPM/ft2. For the NFPA schedule, using 20 ft/sec as the cut-off and 130 ft2 spacing I got an average density of 0.200 GPM/ft2." So having done that it seemed reasonable to flow about 26 GPM/head based on not knowing the water supply, as something to shoot for anyway. Until someone suggests something more reasonable I will go with it, not that it matters in today's world, I am just always wondering why .... Brad -----Original Message----- From: Brad Casterline [mailto:[email protected]] Sent: Monday, September 15, 2014 3:13 PM To: [email protected] Subject: RE: Water Velocity Hilarious Roland. Will do, now that I am done coming up with not only 32 ft/sec, but 20 ft/sec too! And the beer was good (while it lasted). Here is the one I like-- it kills the 7 PSI and the 32 ft/sec birds with one stone: 7/.433=16.166 ft (h). v=SQRT(2gh) = (2*32.2*16.166)^.5= 32.27 ft/sec :) Thanks for the attention sir! Brad -----Original Message----- From: Roland Huggins [mailto:[email protected]] Sent: Monday, September 15, 2014 3:02 PM To: [email protected] Subject: Water Velocity Next time you even start to think of any basis for imposing a velocity of 32 ft/s, take a hammer and smash a finger. Hopefully the pain will divert you from wasting your time especially if you're assuming you are dealing with facts. I've heard numerous conclusion as to why the mystical 32 ft/s existed. Only one has any chance of being valid. Joe Hankins told me long ago that FM initially imposed a velocity restriction after hydraulic calc's entered the scene and folks started designing gridded storage systems with 1 inch BLs. For ever other basis, I can hear Andy Rooney saying - Have you ever wondered why .... Roland Roland Huggins, PE - VP Engineering American Fire Sprinkler Assn. --- Fire Sprinklers Saves Lives Dallas, TX http://www.firesprinkler.org On Sep 12, 2014, at 5:51 AM, Brad Casterline <[email protected]> wrote: > Damien, will you mail me those snaps too please? I have heard the pipe > schedules were derived by increasing the size when the velocity reached > about 32 ft/sec. Figuring out approximate flow per head and average > densities, etc, will give me something to do as I sit at the kitchen table > and drink beer tonight. Thanks. > > Good luck Jeremy! > > Brad _______________________________________________ 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
