DR, I'm not sure how you got your numbers for the underground system.
Also based on your flow requirements of 3233, a 3000 gpm pump would be more than sufficient owing to the fact that the pump can run up the curve to 4500 gpm. I'm looking at 18" pipe, plastic, C-factor of 150, 900 ft of length, at 3300 gpm and I'm getting a .10 psi drop per 100 ft. based on the NFPA calculation methods, total pressure drop for 900 ft of less than 1 psi. A 10" - 12" underground main would have been more appropriate. Craig L. Prahl, CET Fire Protection Group Lead CH2MHILL Lockwood Greene 1500 International Drive Spartanburg, SC 29303 Direct - 864.599.4102 Fax - 864.599.8439 CH2MHILL Extension 74102 [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of dradha Sent: Wednesday, March 19, 2014 12:35 AM To: [email protected] Subject: Re: 20 K16.8 @ 50 + 500 x 120mins Hi Noted your inputs.My assumptions are as follows with k16.8,20 spks and at 50psi remotest pressure works for 2733gpm with 15% addition of hydraulic imbalance. adding 500gpm as hose allowance the total demand is 2733+500=3233gpm. Lets assume the pressure side, the remotest spk pr. is 50psi+line loss 50psi+static loss of44'(19.16psi) upto BOR-bottom of riser. having noted that the pump house is fed by 8" pipe length of 900ft. which is the governing factor to match the requirement of pump discharge head. based on the above info, the pr. reqd at BOR is 120psi with a flow of 3250gpm approx. the selection of the pump should be 3500gpm, with 18" pipe of 900ft requires a pump discharge pressure as 145psi,since to reduce the pressure loss in 900ft length to 20psi. Adding booster pump will not be required,instead change your main pump to 3500gpm at 145psi. If you can send me the layout of the sprinkler drawing and the fire pump location(setting out plan), i can recheck and confirm once again to meet the actual requirement needed for the system. regards DR ae.linkedin.com/pub/radhakrishnan-duraikkannu/38/a05/285/ Regards D RADHAKRISHNAN MANAGER - Engineering & Estimation SAMAY MIDDLE EAST TRADING LLC PO BOX: 128089, Al Quoz Industrial Area-2,Dubai,UAE Tel: 00971 4 3381 200(2 Lines), Fax: 00971 4 3381 300 Mobile: 050-1643785, email : [email protected], [email protected], [email protected],Web site: www.samayprojects.in On Tue, Mar 18, 2014 at 8:50 PM, Gerzayn Fuentes @ CEPI.MX < [email protected]> wrote: > Good morning to all of you. > I have a project for a roll paper storage in a warehouse with 44' height. > The FM Global design is 20 K16.8 @ 50 psi + 500 gpm by 120 minutes. > The fire pump is 2,500 gpm @ 125 psi and the water tank for 269,924 gals. > The preliminary calculations give me 2,130 gals @ 145 psi at the BOR. > The pump room and tank is about 900 ft. from the BOR and have 8" PVP pipe. > The grid system is: 8" primary main, 4" secondary main, 2.5" branch lines. > The sprinkler head are pendent connected through arm-over of 1.5" pipe. > > The issue here is that the distance and Pipe size from the BOR and > Pump give a lot of pressure and velocity. > > What do you recommend to work around? > Booster pump near the BOR? > > Regards! > > ________________________________ > This year we are focused on improving our service ... Your feedback is > extremely helpful. Feel free to support us. > Have a safe day! > > Ing Gerzayn Fuentes Campos | Director > CEPI Specialist in Fire Projects. > Tel +52 (81) 1766-0800 x 106 | http://www.cepi.mx > > Regia Vista # 500 | Linda Vista | Guadalupe | Nuevo Leon | Mexico > | > 67130 > _______________________________________________ > Sprinklerforum mailing list > [email protected] > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkl > er.org > _______________________________________________ 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
