This is going to be for a ESFR warehouse so no standpipes involved. FDC could be connected before or after the PRV. Thanks for everyone confirming that I can install a PRV at a later date.
Sent from my iPhone > On Jul 14, 2018, at 3:12 PM, bcasterl...@fsc-inc.com wrote: > > This is very interesting Dewayne! > You need a high pressure pump now--low pressure pump later, but since you > have to keep the original pump you are thinking PRV on the discharge later. > > There might be another way: > > Replace the big impeller now with a small impeller later. I know how to make > it work in theory but I'm not sure if it works in application, but the pump > rep would. > I know it works in theory because I figured out quite a few years ago how to > calculate the impeller diameter based on the rated psi and rpm ONLY. > I do know it is not unheard of to 'trim' an installed impeller to tamp down > on the psi. > > v=2*pi*r*f, where, > > v is velocity (ft/s) calculated from feet of head (h). v=SQRT(2gh), g is 32.2 > ft/s/s. > r is the impeller radius (ft). > f is radian/s (rpm/60). > > So knowing v and f, it's easy to rearange to solve for r!!! > > You should still install a spool piece I guess, but to pump it up only to let > the air out a couple feet later never has made sense to me. > > Maybe Nicky in NZ knows of something in the European Code that might shed a > different light? > > Brad > > > Quoting Dewayne Martinez <dmarti...@total-mechanical.com>: > >> Is there anything that restricts the use of a PRV after the discharge >> control valve on a fire pump? >> >> I have a ESFR storage building where I am designing to a “future” water >> supply which is much higher than the existing water supply. >> >> The fire pump must satisfy both existing and future conditions and I >> thought about leaving a space for a PRV to be installed downstream of the >> pump discharge valve to account for the future higher pressures. >> >> Thanks, >> >> >> >> Dewayne Martinez >> >> Fire Protection Design Manager >> >> >> >> *TOTAL* *Mechanical* >> >> *Building* *Integrity* >> >> >> W234 N2830 Paul Rd. >> Pewaukee, WI 53072 >> >> dmarti...@total-mechanical.com >> >> Ph: 262-522-7110 >> >> Cell: 414-406-5208 >> >> http://www.total-mechanical.com/ >> >> >> >> [image: A close up of a sign Description generated with high confidence] > > > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list Sprinklerforum@lists.firesprinkler.org http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
