Reza,
The type of your questions did me wonder: Are your questions just
theoretically or are you designing a real life system?
In one of your first messages (3 august this year) you stated that
you are a beginner.
If you are designing for real life you should take notice of NFPA 13
- 2007 paragraph 1.1.2.
In projects where I'm the AHJ, I require that designers and
installers who didn't finish their sprinkler education yet,
are being supervised and their work checked by experienced and
certified designers and technicians.
Answers (how we do it in our office):
1. No, just limited by friction loss.
Yes, 25 sprinklers or more are allowed and it does happen sometimes.
2. In general you would'n't put any sprinklers on the cross mains.
Such sprinklers discharge an excessive amount of water when operated.
Besides that, the cross main itselves creates a dry "shadow"
underneath these sprinklers.
Changes in the sprinkler pattern, due to changes in the building
or the occupancy are more difficult.
I prefer sprinklers near a cross main to be mounted on a
separate branch pipe, even if this means that the branch pipe runs in
parallel with the cross main (but a few feet spaced away from the branch pipe).
3. In general the most economical choice is to design the far main
one size smaller than the near main.
Frans Stoop
TOS architecture & fire protection
Netherlands <[EMAIL PROTECTED]>
At 14:51 2007-09-09 -0700, you wrote:
Hi!
I have some questions about sprinkler gridded systems, thanks for
your attention in advance.
1- Is there any limitation in number of sprinklers to place on
each branch of a wet pipe sprinkler gridded system? Can I put 25
sprinklers on each branch while I am hydraulically calculate the
most remote area?
2- In gridded systems, there are sprinklers on one of the cross
main, am I allowed if I don't place sprinklers on none of the cross
mains? (No sprinkles on cross mains)
3- Do both cross mains have the same size?
Thanks,
Reza
_______________________________________________
Sprinklerforum mailing list
[email protected]
http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum
To Unsubscribe, send an email to:[EMAIL PROTECTED]
(Put the word unsubscribe in the subject field)
