Hey Bruce!
I'm trying to remember back to those old style yard sprinklers - the
green ones with 3 bent arm , some little holes in each, spinning, with
kids laughingly running through it on the 4th of july.
Did those jump up and flip out when you gave them all the spigot had?
Brad
Quoting Bruce Verhei <[email protected]>:
What cave are they in that flex heads are a new thing? In 2018.
While we’re bad mouthing the knot head municipal employee I can
distinctly remember one of the first jobs I was reviewing these for
that was for an open office area, as opposed to a one head clean
cabinet or similar.
I asked why designer hadn’t shown restraining strap, per
manufacturer’s install instructions. I was told I was making things
up, running up the cost of sprinklers beyond what market would bear,
opposing new technologies, the whole normal checklist.
When the rant was done I asked if my best guess was correct. The
heads were already installed. Uh, yeah.
Best.
Bruce Verhei
On May 31, 2018, at 12:57, [email protected] wrote:
Newton's Third Law?
After I fry this fresh cloud based sprinkler applet I'll check your
math Allan and respond off Forum if need be. :)
You know I worked with the inventor of the Hose Monster? He told me
when where and how he got the idea.
I'm the Forest Gump of this industry:
*worked with inventor of sprinkcad
*worked with inventor of autosprink
*worked (and still do) for the first person to print the first
density/area curves for TC consideration.
You can see a pic of him here:
https://www.fsc-icalc.com
Brad
Quoting AKS-Gmail-IMAP <[email protected]>:
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
