Colin, I'm assuming that you are talking old school Underwriters Playpipe. If so, to my knowledge, the standard ripe were 1-3/4 and 1-1/8. Might want to verify the 1-1/4. Also, typically the coefficient is 0.97. Scott is correct that you want to flow more water than that if you can. Suggestion: buy a Hosemonster set up. You can get a 2-1/2" calibrated flow, which is more accurate than an open 2-1-2" butt.
Todd G Williams, PE Fire Protection Design/Consulting Stonington, CT www.fpdc.com 860-535-2080 (ofc) 860-608-4559 (cell) Sent using CloudMagic [https://cloudmagic.com/k/d/mailapp?ct=pi&cv=6.0.64&pv=8.2] On Thu, May 7, 2015 at 10:08 AM, [email protected] <[email protected]> wrote: Colin, The best case scenario is that you flow more water than your highest anticipated sprinkler and hose stream, or in the case of a fire department fire flow requirements. Without knowing your specifics the answer is yes, you should flow more than 386 gpm. Scott Office: (763) 425-1001 x 2 Cell: (612) 759-5556 -----Original Message----- From: Sprinklerforum [mailto:[email protected]] On Behalf Of Colin Carew (Cambridge) Sent: Thursday, May 07, 2015 9:03 AM To: [email protected] Subject: Flow test - Playpipe w/ 1 1/4" Tips Hey All , I just did a flow test last night . Instead of flowing just the 2½ butt and getting the pitot pressure like I have done for years , We used (1) Play pipe with 1 1/4" Tip . When I convert the pito of 70 to GPM with the 0.90 Coefficient to = 363.41 GPM . Should I have flowed both sides with two play pipes to determine a higher flow rate . I have an old flow test from Two years ago that has a flow rate of 1186 Gpm . I am going to do another test next week and just flow the 2½ butt with no playpipes . Colin _______________________________________________ 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 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
