Todd, Regarding the service connection - can't be simpler.
Static Pressure in the Yard and in the Public Street. Flow hydrant in the Yard, Residual Pressure in another hyd in the Yard and in a Hydrant on the Street. Static the same, Residual 40% difference. It is as simple as that. No use for C-Factor: There are Valves, Strainer, Flowmetrer, Backflow Presenter. Dan Dan Arbel Tel: 972-4-8243337 Fax: 972-4-8243278 M: 972-52-2810593 -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Todd Williams - FPDC Sent: Tuesday, February 19, 2008 2:01 PM To: [email protected] Subject: RE: C-Factor for old piping Dan, How are you setting up the test for flowing inside the building? Have you tried running one of these as a hydraulic gradient and empirically determining the C factor? What pipe materials are being used? If what you are concluding is correct, then should we be using a C factor of 84 instead of 140 for underground calcs. At 06:33 AM 2/19/2008, you wrote: >I think I was misunderstood, because I raised two issues concerning the >reliability of the calculations and mfg data. > >A. New systems and >B. Old systems. > >NEW SYSTEMS: > >In tests made across new service connections I got pressure losses ranging >from 30% to 45%. Just last week on a brand new system I got 40% loss. > >Imagine a designer advising the principal that he can construct a warehouse >with reliance on the public supply providing 910 gpm for sprinklers based >upon ample water from the Public Supply, all based on Public Supply testing >on the street and hydraulic calculation. > >Then, after completing the system, test is made next to the Risers and it >appears at the design pressure there is only 600gpm available. > >The flow test was made inside the premises; residual pressure was measured >both within the premises and in the street. > >The residual pressure within the premises was lower 40% from that on the >street. All valves are open and there is no explanation based on Mfg data >and any calculation. > >Now think about the liability of the people involved. > > >OLD SYSTEMS: > >A total different situation is the old pipe. There I got loss of 75%. > >In one location there was a design of ESFR requiring 1750 gpm. In order to >get that the principal had to replace a pump and to install 1500-2000 gpm >pump. > >The test I made on behalf of Insurer proved that the mains can deliver only >500gpm at the required pressure. > >In another location, 6" connection from a pump to risers, the demand was >1780 gpm at 110 psi. The actual measured supply was 400 gpm at 110 psi. > >Dan > > >Dan Arbel >Tel: 972-4-8243337 >Fax: 972-4-8243278 >M: 972-52-2810593 >-----Original Message----- >From: [EMAIL PROTECTED] >[mailto:[EMAIL PROTECTED] On Behalf Of Ron Greenman >Sent: Monday, February 18, 2008 8:15 PM >To: [email protected] >Subject: Re: C-Factor for old piping > >There are the two extremes Dan was originally talking about. Old pipes >with a 140 and old pipes with 40% degradation. Then you get the water >purveyor that won't let you touch his stuff at all or at best will >only allow flow testing at midnight (what percentage do you add to get >a decent picture of peak use?) and only if you capture the water and >process out the chlorine he put in it. Or he'll give you water data on >a 50s system that was done in 1986 from a hydrant somewhere close. Or >he'll model flow by computer since somehow his modeling data can >magically disspell all the concerns we've been talking about for the >past few days. And, by the way, running that program will take four to >six weeks. On top of that nobody from the A&E team is going to take >responsible charge and the GC who just accepted (verbal, not signed) >George's design/build proposal didn't do it until two days before >GEORGE was supposed to start and now George is holding up the project. >And somehow we manage to get out a product with a huge success rate in >spite of all that, public apathy, owner hostility and often spotty >maintenance. There are few days that pass when I'm not sure that >running a hot dog stand isn't a better idea. > >On 2/18/08, George Church <[EMAIL PROTECTED]> wrote: > > Only time I had a requirement that we felt was obscene to degrade an > > existing UG loop - the local AHJ wanted us to use like C=90 for 1960's (?) > > UG loop around a plant being rebuilt after roof collapse (snow). > > > > Part of our work included cutting out a section of te existing UG and we > > left a piece of the existing sitting there for the AHJ to examine; it was > > clean as a whistle and he then, if memory serves me correctly, C=140 or at > > least something closer to reality (and not requiring a booster pump after > > the booster pump). Call it a flow test by visual examination:) > > > > glc > > > > -----Original Message----- > > From: [EMAIL PROTECTED] > > [mailto:[EMAIL PROTECTED] On Behalf Of Roland > > Huggins > > Sent: Monday, February 18, 2008 12:24 PM > > To: [email protected] > > Subject: Re: C-Factor for old piping > > > > agreed. AS already stated by others, old underground water supplies > > require a flow test to assign a reliable C value. Let's not forget > > to assign a continued amount of degradation if the existing > > conditions are accepted verses designing to what is tested today. I > > must confess not exactly sure what NFPA 24 says (if anything) since > > that memorized text is assigned to a portion of the memory bank that > > is not longer accessible. > > > > Roland > > > > On Feb 18, 2008, at 8:43 AM, [EMAIL PROTECTED] wrote: > > > > > We > > > certainly cannot go to the design standard as it is designing with new > > > pipe. So, what is the answer? > > > > _______________________________________________ > > 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) > > > > >-- >Ron Greenman >at home.... >_______________________________________________ >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) > >No virus found in this incoming message. >Checked by AVG Free Edition. >Version: 7.5.516 / Virus Database: 269.20.7/1285 - Release Date: 18/02/2008 >05:50 > > >No virus found in this outgoing message. >Checked by AVG Free Edition. >Version: 7.5.516 / Virus Database: 269.20.7/1285 - Release Date: 18/02/2008 >05:50 > > >_______________________________________________ >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) No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.20.7/1285 - Release Date: 18/02/2008 05:50 No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.20.7/1285 - Release Date: 18/02/2008 05:50 _______________________________________________ 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)
