Easy to do with a dead end system but not so easy with a gridded system
*Thanks* *Rahe Loftin, PE * *Regional Fire Protection Engineer* *General Services Administration* *Region 7 - TX, OK, NM, AR, LA* *Facilities Management & Support 7PMC* *c - 817-371-3102* *o - 817-978-7299* On Thu, Jun 26, 2014 at 11:58 AM, Brad Casterline <[email protected]> wrote: > Makes sense Todd. > > I believe a flow test measures the friction loss from the source to the > gauged hydrant, with a negligible amount of velocity head loss. Say we get > 75,72,500. If we know 8" X 1500 feet total, using Q^1.85 and rearranging > H-W, we can get the C-Factor=140. If we got 75,68,500 with the same 8 by > 1500, we would get C=85. Also, using Q^2 and C=140, we would get the same 7 > pound drop. I guess what I am saying is, the flow test is a measure of the > several factors, as a whole, that are usually unknown without doing a lot > of > digging, literally ;) > > Brad > > > -----Original Message----- > From: Todd - Work [mailto:[email protected]] > Sent: Thursday, June 26, 2014 10:18 AM > To: [email protected] > Subject: Re: Underground Piping > > Remember, all of our formulas are approximations. They can be more accurate > in some situations and less in others. The velocity restrictions of years > back were originally to compensate for the inaccuracies in the formula when > velocity exceeded a certain amount. > > Todd G Williams, PE > Fire Protection Design/Consulting > Stonington, CT > www.fpdc.com > 860-535-2080 (ofc) > > > _______________________________________________ > 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
