I would look at it like this: The discharge gage is like the flow test hydrant that you are calcing to. The test header is like the remote area with a PSI and GPM demand, and the test header pipe, fittings, and hose is between the two points. The pitot gage reading at the test header is measuring the velocity pressure so the velocity can be determined in ft/sec, times square feet nozzle area (times .97), to give ft3/sec, or GPM.
-----Original Message----- From: James D. Waite [mailto:[email protected]] Sent: Thursday, September 19, 2013 9:47 AM To: [email protected] Subject: RE: Fire Pump Test Header Calculation Right. So the worksheet from NFPA 20 basically calculates a total amount of friction loss from the pump to the pitot. So, my discharge gauge shows the total of the pump pressure and the city supply. I use the worksheet to calculate a total friction loss. Would the total calculated friction loss have to be less than the reading on the discharge gauge? Or, would the friction loss have to be less than the discharge gauge reading minus the pump's added pressure (i.e. the city supply)? How does this calculation relate to the flow being measured? Or are the two unrelated? Jimmy Waite, CET - Design Manager Fire & Life Safety America- Raleigh District 7711 Welborn Street, Suite 103 Raleigh, NC 27615 Office: 919-872-3250 Cell: 919-868-3546 Fax: 919-877-5775 www.flsamerica.com -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Brad Casterline Sent: Thursday, September 19, 2013 6:17 AM To: [email protected] Subject: RE: Fire Pump Test Header Calculation Jimmy, I would guess that if your pump discharge PSI at the 150% rated GPM test flow (from the pump curve) is higher that what you calculated for the required pump discharge, you have proved it-- (demand is 'under the curve' using that pipe size). -----Original Message----- From: James D. Waite [mailto:[email protected]] Sent: Wednesday, September 18, 2013 6:10 PM To: [email protected] Subject: Fire Pump Test Header Calculation Can I get some assistance with a fire pump test header calculation? I got the calculation form from 20:4.20.3.4, and I have it filled out. But what to I do next? How do I use it to confirm the pipe size? Jimmy Waite, CET - Design Manager Fire & Life Safety America- Raleigh District 7711 Welborn Street, Suite 103 Raleigh, NC 27615 Office: 919-872-3250 Cell: 919-868-3546 Fax: 919-877-5775 www.flsamerica.com<https://owa.flsamerica.com/owa/www.flsamerica.com> ________________________________ The information contained in this email and any attached documents may contain information that is the confidential property of Fire & Life Safety America, Inc ("FLSA"). Any documents created on any FLSA computer or by any employee in the conduct of FLSA business is work product and owned by FLSA. If the reader of this message is not the intended recipient, or the employee or agent responsible to deliver it to the intended recipient, you are hereby notified that any dissemination, distribution or other use of the contents of this communication is strictly prohibited. If you have this communication in error, please immediately notify the sender and delete this email. _______________________________________________ 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 ________________________________ The information contained in this email and any attached documents may contain information that is the confidential property of Fire & Life Safety America, Inc ("FLSA"). Any documents created on any FLSA computer or by any employee in the conduct of FLSA business is work product and owned by FLSA. If the reader of this message is not the intended recipient, or the employee or agent responsible to deliver it to the intended recipient, you are hereby notified that any dissemination, distribution or other use of the contents of this communication is strictly prohibited. If you have this communication in error, please immediately notify the sender and delete this email. _______________________________________________ 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
