How is making bigger holes on the discharge end going to change the velocity in the 1.25" service pipe if the flow is a constant?
Craig L. Prahl, CET Fire Protection CH2MHILL Lockwood Greene 1500 International Drive Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 CH2MHILL Extension 74102 [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ron Greenman Sent: Monday, April 04, 2011 1:38 PM To: [email protected] Subject: Re: Design solution needed With this little pipe velocity is the problem. I'm using the bigger holes to require less pressure at the end head and so slow the water down that's passing through the narrow pipe. Given the restriction of the pipe and the constant calculated demand of 0.15/X (900 or 1500) this may do nothing but my in head estimator isn't well calibrated either. On Mon, Apr 4, 2011 at 10:09 AM, Morey, Mike <[email protected]> wrote: > K8 heads could actually penalize his design in the OH-I area couldn't they? > 7 psi minimum end head dictates 14ish GPM out of a k5.6, even at 130 sq ft > going to a K8 head would actually cause him to discharge more GPM than the > density requires (at least using my not particularly well calibrated internal > calculator), and GPM as we know is what creates friction loss. In the LH > area if he spaced the heads out near the limits a K8 will save him some > pressure, but given his water supply that doesn't look to be his biggest > concern. The big question is how long the 1 1/4" run is in my mind, if it's > short enough you can jump up at the connection, if it isn't then you don't > have a lot of options unless maybe you can squeeze out some area reductions > (QR/Ceiling height reductions if they haven't been considered) with careful > code reading and head selection. > > Mike Morey, SET > Sprinkler Designer > BMW Constructors, Inc. > O: 317.651.0596 | C: 317.439.2695 > www.bmwc.com > <https://owa.bmwc.com/exchweb/bin/redir.asp?URL=http://www.bmwc.com> > > > ________________________________ > > From: [email protected] on behalf of Ron Greenman > Sent: Mon 4/4/2011 12:49 PM > To: [email protected] > Subject: Re: Design solution needed > > > > What K heads are you using. Bigger holes help more than bigger pipes > in good pressure/bad water situations. If you're using K5.6 see the > huge gain K8.0 will give you. And your moister recent post asked most > of the questions I asked just as that left and yours arrived. > > > > _______________________________________________ > 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) > -- Ron Greenman Instructor Fire Protection Engineering Technology Bates Technical College 1101 So. Yakima Ave. Tacoma, WA 98405 [email protected] http://www.bates.ctc.edu/fireprotection/ 253.680.7346 253.576.9700 (cell) Member: ASEE, SFPE, ASCET, NFPA, AFSA, NFSA, AFAA, NIBS, WSAFM, WFC They are happy men whose natures sort with their vocations. -Francis Bacon, essayist, philosopher, and statesman (1561-1626) _______________________________________________ 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) _______________________________________________ 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)
