This puts the hydrant outlet at least 10 feet below the base of the tank. Otherwise the residual pressure would not be possible?
Bill Brooks William N. Brooks, P.E. Brooks Fire Protection Engineering Inc. 372 Wilett Drive Severna Park, MD 21146 410-544-3620 Phone 410-544-3032 FAX 412-400-6528 Cell -------- Original Message -------- Subject: RE: water storage tank From: <[email protected]> Date: Thu, August 06, 2009 4:04 pm To: <[email protected]> FWIW: I was digging through some old project data where we had some flow information from a similar arrangement. The 250,000 gallon elevated tank, B.O.T. was 140ft, with a 10" riser serving a 10" underground fire main. Residual flow at the hydrant nearest the tank revealed approximately 2100 gpm at 65 psi. Loss through the 10" riser using HW would indicate about a 1.7 psi loss for the 140 ft. And BTW, the risers are usually steel not DI. So different C-factor, makes a little difference in the loss. Craig L. Prahl, CET Fire Protection Specialist Mechanical Department CH2MHILL Lockwood Greene 1500 International Drive PO Box 491, Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 [email protected] http://www.ch2m.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Mark Sornsin Sent: Thursday, August 06, 2009 3:36 PM To: '[email protected]' Subject: RE: water storage tank The correct calculation is 0.156 x 14 not 140 (the formula given earlier was 0.156 psi/10 ft.). So your loss through 140 ft. of cement lined ductile iron would be 2.2 psi at 1,560 gpm. [that loss per foot of DI pipe seems a little high to me, but its prolly good enough for these purposes] Mark A. Sornsin, PE Fire Protection Engineer Ulteig Engineers, Inc. Fargo, ND Direct: 701. 280.8591 [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Greg McGahan Sent: Thursday, August 06, 2009 1:37 PM To: [email protected] Subject: RE: water storage tank You are correct....the answer I got was "we don't know"........from the horse's mouth. Thanks for all of your help, I will let you know how it works out in a few hours. Greg McGahan Operations Manager Living Water Fire Protection 1160 McKenzie Road P.O. Box 877 Cantonment, Florida 32533 (850) 937.1850 | Fax (850) 937.1852 | Cell (850) 554.3231 [email protected] -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Todd Williams Sent: Thursday, August 06, 2009 11:04 AM To: [email protected] Subject: RE: water storage tank Someone designed a water tank and they can't tell you the output? Who sold that design contract? At 11:18 AM 8/6/2009, you wrote: >I am getting info piecemeal from the engineering firm that is in charge >of the tower. They say they don't Know what the residual pressure and >flow will be when the tower is completed. We have a sprinkler system >going in "next door" to the tower using the existing water from the old >system. However, they have installed a 4" pipe with a hydrant instead >of 6" (many years ago)and nobody knew until we dug it up. > >Now we are flowing 600 gpm through a 4" pipe to our source and the >calcs are too close for comfort. We are looking for a "guesstimate" >of the available water at the base of the tower without any fittings or >valves. I can add them in the 8" line from the base to the new tie in >point where the systems tie together. We are talking about needing to >pick up 5 to 10 psi not 20 or 30, so as long as we are close we should >be good. > >This really should fall on the EOR, but as is often the case in this >region, if we want to finish the job on time, we have to get an answer >immediately. > >So I can say that I should reasonably be able to expect .156 x 140' >= 22 lbs of loss from the tank to the bottom w/o fittings....therefore >if we say we should reasonably expect 1,500 gpm at 35 psi? > _______________________________________________ Sprinklerforum mailing list http://lists.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 http://lists.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 http://lists.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)
