How do you calculate GPM on an automatic nozzle? If NP is 100psi what GPM am I getting out of my nozzle? Our nozzle does not indicate GPM at a psi only a range of 50 to 300 GPM.
A pump operator must do a friction loss calculation, since he is the only one that can regulate the flow. The desired flow must be determined in advance, friction loss calculated for that flow, added to required nozzle pressure, and the sum will be the pump discharge pressure
i don't understand the part where, If you are getting 60psi from the pump, and the nozzle is set to 75 psi, then you will flow 75 psi. How can you get more from less?
Think of it as a regulator. If it is getting 60 psi from the engine, it will cause a back up in the line to increase that 60 psi to 75 psi. If it is getting 100 psi from the engine, the nozzle will back it down to 75 psi. Hope that helped.
