Automcatic Fire Sprinkler System

[GabSantos21]

Hi!

I am currently designing an AFSS for a school requirement. I would like to ask if you can put sprinklers in the main cross? I designed my main cross to run along the corridor of the building. can i put my sprinklers in the main cross?

Thank you in advance!

 

[MatthewJWillis]

Yes.

R/
Matt

 

[GabSantos21]

hi, matthewJwillis

one more question, is it necessary to run your cross main along the long side of the building? also,I am having trouble in assigning the diameters of my pipe. According to NFPA 13, the pipe schedule method is based on how many sprinklers are to be supplied. but I am using hydraulically designed method, How can I assume the size of the pipes?

Thank you.

 

[MatthewJWillis]

Those follow up questions prompt one of my own.
Are you a Sprinkler Contractor?
Not being rude, but those questions are a little beyond what I feel can be answered here..


R/
Matt

 

[GabSantos21]

I'm not a contractor. I am a civil engineering student. I have this requirement that needs an AFSS design. I'm just here looking for some help on things I don'd understand much.

well, thank you for your help anyways.

R/
Gab

 

[MatthewJWillis]

No worries.
I read "AFSS for a school requirement" as you were designing a school.
Still, the answers to those questions are developed based on many variables.

Chapter 3 of NFPA 13 is where I'd start. That sets the base.
Then the rest of the Standard. I will caution, it is very confusing and is normally done under direct, senior experience supervision.

Good luck.

R/
Matt

 

[dbill74]

First thing, these forums are not intended for help with homework/school assignments. You really need to be raising these questions in class and with your professor.

That said and your question not being "solve my problem for me".

one more question, is it necessary to run your cross main along the long side of the building?

No, but tends to be most cost effective and convenient.

I am having trouble in assigning the diameters of my pipe. According to NFPA 13, the pipe schedule method is based on how many sprinklers are to be supplied. but I am using hydraulically designed method, How can I assume the size of the pipes?

Use pipe schedule method as a starting point for doing hydraulic calculations. Sizes from the schedule method will usually be within 1-2 pipe sizes of what hydraulic calculations end up with.

 

[TravisMack]

Typically the cross mains run parallel to the structure and the branch lines run perpendicular. That is for ease of hanging in most cases.

As long as you are calculating your most demanding area, you are creating your own pipe schedule. You are sizing the branch lines for the calculated area and then you are sizing the main to deliver that amount of water to that area. Size the rest of your branch lines based on the same schedule that you developed in your calculations.

You can put sprinklers on a cross main, but you need to look at the obstruction rules about having upright sprinklers on certain sizes of pipe. Chapter 8 will be your friend for this stuff.

Good luck on your assignment. I'm glad to see schools actually teaching some of this in a civil engineering program.

Travis Mack
MFP Design, LLC

http://www.mfpdesign.com

"Follow" us at

https://www.facebook.com/pages/MFP-Design-LLC/92218417692

 

[cdafd]

GAB

Do you know about trees, looped, gridded?

 

[GabSantos21]

Thank you for your response.