https://www.youtube.com/watch?v=n5fJ1lCVE98
Looks like a decent kick to me. Scott >> So what is this jet effect that is going to lift the sprinkler? The forces >> on this sprinkler are going to be the end pressure force and any momentum >> change force. >> >> Lets say this is a 5.6k sprinkler having a .438” diameter orifice. The >> orifice area is about 0.1507 square inches. That is about 1lb for 7 psi and >> about 12 lbs for 80 psi since those pressure numbers are gage pressure >> referenced from atmosphere pressure. The orifice end pressure force must be >> why we have the last sprinkler surge restraint rule where there is not much >> piping for counter balance. >> >> Now what is the momentum change? The water comes streaming out the nozzle >> and slams into the deflector that is connected to the nozzle. There is a >> canceling out. Then the water changes momentum to go radially. Lets say that >> is equal in all directions. So the radial momentum changes cancel each >> other. Think of a Hose Monster. The momentum change situation is not the >> same as that of hose nozzle stream needing some beef to hold it. >> >> It would not take much to demonstrate this. Take a flex drop and operate it >> with an open sprinkler and compare to operating it also with a busted off >> sprinkler that has no deflector and arms. Pick a nice hot day to do this. >> >> >>> On May 30, 2018, at 10:59 AM, Richard Mote <[email protected]> >>> wrote: >>> >>> I have a AHJ <> that is questioning the use of Flex Drops especially the >>> Victaulic ones. He says that they are so flexible that when a sprinkler >>> goes off the jet effect is going to lift the sprinkler up through the >>> ceiling. I told him that the drops are mechanically attached to the ceiling >>> grid and in order to lift up they would have to lift the entire weight of >>> the ceiling grid, ceiling tiles, the lights and HVAC diffusers. His answer >>> prove, it either by letter from the manufacturer or from someone a lot >>> higher up the food chain than either he or I am. Or something specific in >>> NFPA <> 13 that says he is wrong. >>> >>> Richard Mote >>> Design Manager >>> >>> W: 877.324.ROWE · F: 570.837.6335 >>> PO Box 407 · 7993 US Route 522, Suite 1 · Middleburg, PA 17842 >>> 505 A Cornerstone Court · Hillsborough, NC 27278 >>> RoweSprinkler.com · [email protected] >>> <>_______________________________________________ >>> 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 _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
