Tom, Do you know why the Pollards are in accurate? I have read that there is problem with the pitot being inside a short tube.
Ron Fletcher Aero Automatic Sprinkler Phoenix, AZ -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tom Duross Sent: Wednesday, October 15, 2008 5:55 AM To: [email protected] Subject: RE: FLOW / PITOT READINGS What Steve said plus get rid of that pollard diffuser, very inaccurate. Use a couple of playpipes if you don't have a monster. Tom A pitot measures velocity pressure, which is converted to flow in GPM per the formula already posted by others. Residual is the pressure left in the main when it is flowing a fixed amont of water, such as might be measured with a pitot. See NFPA 291; in the standard 2 hydrant flow test, the pitot and residual are measured at separate hydrants. _______________________________________________ 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)
