So the tank is needed for head pressure? Sounds unusual. Normally the pump is sized to operate off of essentially zero suction from the tank. If the design basis of this pump needs the head pressure from the tank, and if the fill rate equals the discharge rate, all you need is a 10-inch diameter tank that is tall enough. It is more likely that the tank was sized from the sprinkler design.
John Hoffman, PE Facility Engineering Services KCP, LLC -- Burns & McDonnell Engineering National Nuclear Security Administration's KC Plant Operated by Honeywell FM&T, LLC office: 816-488-7213 [email protected] -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Karen Lesko Sent: Friday, June 13, 2014 9:05 AM To: [email protected] Subject: RE: 2 hour fire water supply I don't know what the design basis was, but it looks like we need the automatic fill to maintain the head pressure, so probably not. On Fri, Jun 13, 2014 at 8:20 AM, Brad Casterline <[email protected]> wrote: > Karen, > Sorry about the superfluous talk about fire- I was watching it all > play out in my mind (fast forwarded because 2 hours is a long time)- > but this is interesting in that the fill rate is equal to the > discharge rate, so it is no different than a city water flow test, > except you need a fire pump for pressure. > Was the water storage tank capacity arrived at based on system demand > for 2 hours, with no consideration of automatic fill? > Brad > -----Original Message----- > From: Brad Casterline [mailto:[email protected]] > Sent: Thursday, June 12, 2014 9:14 PM > To: [email protected] > Subject: Re: 2 hour fire water supply > I see accidental fires, Sprinklered or not, going through three phases: > erratic growth, somewhat steady burning, then some sort of decay. If > you look at what might be the lowest water level in the tank over two > hours would be you could get an idea of what the minimum pressures at > the sprinklers would be. >> On Jun 12, 2014, at 9:01 PM, Brad Casterline >> <[email protected]> > wrote: >> >> Probably not since there is a difference between the total capacity >> and > the available head at any one instant in time? >> >>> On Jun 12, 2014, at 8:40 PM, Karen Lesko <[email protected]> wrote: >>> >>> When evaluating fire water supply to ensure there is a 2 hour >>> supply, do > I >>> have to take the head pressure loss of the fire water tank level >>> drop > into >>> account over the 2 hours? The tank has makeup from wells that have > normal >>> and back-up power, and the well makeup into the fire water tank >>> equals > the >>> output of the fire pump. >>> >>> Thank you in advance, >>> >>> Karen Lesko >>> _______________________________________________ >>> 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-firesprinkl > er.org _______________________________________________ > 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-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
