NOW I see all this neat stuff long after I've gotten too old and decrepit to put it to use! Oh well, maybe it's time to pick up my pen and pencil and draw about it again, using this and my own experiences as a guide. Thanks guys! You're reinvigorating my soul again! I loved being a volunteer firefighter (1979-2004)!
Depends a ton on the lengths and flows of each line. You are reducing volume, so there will be a lot less friction loss in the 2.5", but the 1.75" does have quite a bit more friction loss in it. Friction loss from the nozzle, coefficent on the hoses, target flows of each line, and lengths of each hose all cause variation. Some flow testing can help you build a good pump chart and make this simple to reference. One example from my dept's particular set up: 200' of 2.5" with 265 gpm (1 1/8" tip at 50psi) is a PDP of 80 psi. Putting 100' of 1.75" with a 160 gpm nozzle would need a PDP of 90 psi, so a slight increase in pressure is called for in that case.
NOW I see all this neat stuff long after I've gotten too old and decrepit to put it to use! Oh well, maybe it's time to pick up my pen and pencil and draw about it again, using this and my own experiences as a guide. Thanks guys! You're reinvigorating my soul again!
I loved being a volunteer firefighter (1979-2004)!
Good Stuff ! The Art of using the 2.5 Handline is a Lost Art that needs to be restored to the Fire Service of today !
Does the pump operator need to increase pressure to account for the additional 1.75" attack line being added to the system?
Looks like they only added a 50 foot length, that won’t change things much.
Depends a ton on the lengths and flows of each line. You are reducing volume, so there will be a lot less friction loss in the 2.5", but the 1.75" does have quite a bit more friction loss in it. Friction loss from the nozzle, coefficent on the hoses, target flows of each line, and lengths of each hose all cause variation. Some flow testing can help you build a good pump chart and make this simple to reference. One example from my dept's particular set up: 200' of 2.5" with 265 gpm (1 1/8" tip at 50psi) is a PDP of 80 psi. Putting 100' of 1.75" with a 160 gpm nozzle would need a PDP of 90 psi, so a slight increase in pressure is called for in that case.
@@randyayo2846 He did say two lengths.
yes they gotta calculate the friction lost they just gotta add 20 psi so they have the right pressure
Second hose connected no need to layout again, just leave it so then it will pop up by itself then just drag it