I once tried to get the velocity in a pipe to the speed of light. (It was a slow day) 1,000,000 psi pressure, 10,000,000 gpm flow, thru a 1/8" piece of pipe. Didn't come close, but it was fun to see what HASS spit out. Thom, you are right, the system will flow what it will flow. 100 psi at the end head of a 1" line is still flowing 56 gpm regardless of what the calcs say in demand mode. Always liked the supply vs demand calc. Jamie Seidl -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Todd Williams - FPDC Sent: Monday, June 02, 2008 11:51 AM To: [email protected] Subject: Re: High velocities
It sounds like I'm the only one out there not designing systems with Mach 3 velocities. There has to physically be some upper limit to what a pipe can carry. You're not going to get 800 gpm through a piece of 1", even though you can calculate the friction loss with HW. Where is the practical limit? (Joe may be able to shed some insight. hint, hint....) At 11:27 AM 6/2/2008, you wrote: >The formula that I was taught some time back is, Pu = $s (pressure unused >equals dollars spent). > >BK > >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] On Behalf Of Fletcher, Ron >Sent: Monday, June 02, 2008 9:12 AM >To: [email protected] >Subject: RE: High velocities > >Burn it up! > >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] On Behalf Of Chris >Cahill >Sent: Monday, June 02, 2008 7:47 AM >To: [email protected] >Subject: High velocities > > > >A question for where there is healthy pressures. Around here 60 is >considered high. I know places with 28 static. > Got a OHII system that needs to be changed to EXII. > That's not negotiable. It's a 40 yo pipe schedule system. That >appears to be in good shape. The BL need to be replaced for 100 sq.ft. >but the main even the last 12' >of 2.5", 25' of 3" and 36' of 3.5" can fly without being replaced. The >openings are where I need them. There is a FP with about 140 psi at the >900gpm demand. The "problem" >is the velocities in one segment of pipe are just about 40 (last piece >of 3") and about 30 in the 3.5". I quote problem because I know 13 has >no limit, this is not FM. > There is still better than 15 psi safety. > >So the question is where you have pressure do you typically burn it up >with small pipe size at the cost of velocities getting high or do you >leave a lot of safety? > Again not FM and OK per 13. > >Any thoughts on why this is a bad idea? It's easy to say just pull the >offending pipe. In reality though you all know the competitive market >and spending owners money. > > >Chris Cahill, P.E. >Fire Protection Engineer >Sentry Fire Protection, Inc. > >763-658-4483 >763-658-4921 fax > >Email: [EMAIL PROTECTED] > >Mail: P.O. Box 69 > Waverly, MN 55390 > >Location: 4439 Hwy 12 SW > Waverly, MN 55390 > >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum > >To Unsubscribe, send an email to:[EMAIL PROTECTED] >(Put the word unsubscribe in the subject field) Todd G. Williams, PE Fire Protection Design/Consulting Stonington, Connecticut www.fpdc.com 860.535.2080 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
