I'd guess in the 350 to 400 gpm range if your main drain was attached directly to the riser off a tee then 2" angle valve then drop to floor. This is about 70 equivalent ft in length. With 100 psi at the riser you'd see a loss of 85 psi between the riser and the main drain outlet leaving around 15 psi at the outlet of the 2" pipe. Since a 2" pipe has approximately 17 times the area of a 1/2" sprinkler I'd multiply 22 gpm times 17 to get 374 gpm.
Purely seat of the pants but old seat in pants. Bill Brooks William N. Brooks, P.E. Brooks Fire Protection Engineering Inc. 372 Wilett Drive Severna Park, MD 21146-1904 410-544-3620 410-544-3032 FAX 412-400-6528 Cell -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Tuesday, August 02, 2011 3:02 PM To: [email protected] Subject: How much discharge from a 2" system drain Plumbing engineer is asking how much flow could come from a 2" main drain at the riser. They are sizing floor sinks to capture the discharge. No we're not discharging it outside like usual. This isn't a "usual" client. System pressures from the pump are around 200psi static and 180 psi residual. That's a whole other issue. Craig L. Prahl, CET Fire Protection CH2MHILL Lockwood Greene 1500 International Drive Spartanburg, SC 29304-0491 Direct - 864.599.4102 Fax - 864.599.8439 CH2MHILL Extension 74102 [email protected] _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.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 [email protected] http://fireball.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)
