One other item you should be aware of; is not to exceed 15ft/sec in velocity head on the suction side. NFPA 20 2010 4.14.3.3
Ed Cyr Alpha Fire San Luis Obispo, CA On Tue, Jun 7, 2011 at 9:28 AM, Ralphy Henderson <[email protected]>wrote: > Bob, > > That's kind of what I was getting at. I'll probably just have to submit a > separate calc showing the 150% pump rating through the pump to the tank to > prove the losses are acceptable. Does anyone know if there is a way to do > this in a single calc in hydracalc? I can put in an additional water > 'source' but then would have to enter in a static, res, and flow for the > tank to get it to run through the program and these numbers are unknown > (except for static). > > Thanks, > > RB > > > --- On Mon, 6/6/11, Bob <[email protected]> wrote: > > From: Bob <[email protected]> > Subject: RE: Pump, Tank, 1000 ft suction line..... > To: [email protected] > Date: Monday, June 6, 2011, 11:05 PM > > Ralph, > Looking at this I'm coming up with 20.3 psi loss in 1000' of pipe not > counting fittings and valves. > (4.52*1000.00^1.85)/(140^1.85*6.4^4.85) = .0203 .0203 * 1000 = 20.3. > 6.4" is ID of 6" Tyton Joint Pipe DI. Fittings and valves will increase > your losses. At 1500 gpm you will have .43 psi / ft loss. These numbers > will vary depending on pipe type and ID. > As far as how to do it; I think I would simply run the numbers through the > calculation back to the tank. Or better yet, if there are hydrants fed off > of the tank have a flow test performed and calc back to that point of > connection. > > Bob Knight, CET III > 208-318-3057 > www.firebyknight.com > > > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Vince > Sabolik > Sent: Monday, June 06, 2011 4:37 PM > To: [email protected]; [email protected] > Subject: Re: Pump, Tank, 1000 ft suction line..... > > Ralph - > > My rough calcs say about 16 psi loss at 100% flow and 34 psi loss at 150% > flow. > Unless this is an elevated tank, or your source is uphill from the pump, > this won't work. > > At 06:32 PM 6/6/2011, you wrote: > >at 1000 gpm, you are going to lose about 2 psi per 100' of 6" > >ductile iron pipe. At 1500 gpm, you are going to lose about 5 psi / > >100' of DI pipe. You need to have enough elevation between the tank > >and pump to provide a positive pressure at the suction flange. > > > >On 6/6/2011 3:28 PM, Ralphy Henderson wrote: > >>Hi All, > >> > >>Can someone explain to me how one would go about calculating a fire > >>pump being fed solely from a water storage tank but with a 6" x > >>1,000 ft suction line? I've calculated fire pumps off of tanks that > >>had a small 10 ft. suction lines directly off the tank but never one > >>with this amount of underground line and I'm concerned about making > >>sure friction losses in the suction are properly accounted for. The > >>pump is 75 psi @ 1000 gpm. > >> > >>We use hydracalc, and typically when a fire pump and tank scenario > >>comes up we have only one 'source', the pump, being specified. > >>Would this change in this instance? I guess the main thing I'm > >>concerned about is coming up with a negative pressure at the suction > >>flange due to such a long run. > >> > >>Any help? > >> > >>-RB > >> > >>_______________________________________________ > >>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) > > > >__________ Information from ESET NOD32 Antivirus, version of virus > >signature database 6185 (20110606) __________ > > > >The message was checked by ESET NOD32 Antivirus. > > > >http://www.eset.com > > > > > > Vince Sabolik > Christi Fire Protection, Inc. > 11351 Pearl Road > Strongsville, Ohio 44136 > > T 440 572-7730 F 440 572-7719 Email: > <mailto:[email protected]>[email protected] > > _______________________________________________ > 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) > _______________________________________________ > 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)
