If it's only about a foot, it probably isn't critical. If it had been closer to 10', that could have kept the pressure at the pump suction closer to -3 psi. Someone may need a larger suction pipe.
> -----Original Message----- > From: [EMAIL PROTECTED] [mailto:sprinklerforum- > [EMAIL PROTECTED] On Behalf Of A.P.Silva > Sent: Friday, October 31, 2008 11:55 AM > To: [email protected] > Subject: RE: Fire Pump Suction > > Maybe a foot or so. I'm just guessing. Will have to find out if it is > critical. > > Tony > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Ed Kramer > Sent: October 31, 2008 9:45 AM > To: [email protected] > Subject: RE: Fire Pump Suction > > How much higher are the tank discharge flanges above the pump suction > flange? > > Ed Kramer > Littleton, CO > > > -----Original Message----- > > From: [EMAIL PROTECTED] [mailto:sprinklerforum- > > [EMAIL PROTECTED] On Behalf Of A.P.Silva > > Sent: Friday, October 31, 2008 11:32 AM > > To: [email protected] > > Subject: Fire Pump Suction > > > > > > 400 gpm fire pump supplied from tanks with suction flanges higher than > > pump suction flange. Approximately 100 feet of 4" piping (including > > fittings) from tanks to pump. NFPA 20 permits the gauge pressure at > > the pump suction flange to drop to -3 psi, with the pump flowing at > > 150% (600 gpm in this case). The friction loss in the piping for 600 > > gpm flow is about 7.6 psi. Is there a concern for the pressure > > available at the pump suction, when the water level drops in the > > tanks? I have been told that it will, so checking the opinion of the > > forum. > > > > Tony > > > > _______________________________________________ > > 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:Sprinklerforum- > > [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:Sprinklerforum- > [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:Sprinklerforum- > [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)
