Are you talking about picking initial sizes prior to doing hydraulics? If that is the case, keep it simple. For commercial spaces, I typically start with either all 1-1/4" or pipe schedule branch lines and 4" mains and go from there. Grids, a 4x3x1-1/2 or 6x6x2 for storage. Most hydraulic programs will allow you to shuttle between pipe sizes quickly and adjust to what you actually need. It doesn't matter where start from, just as long as where you end up is correct.
If you are talking about final sizing, use either hydraulic calculations or pipe schedule sizes. Anything else is opening yourself up to way too many problems. At 04:23 PM 2/10/2010, you wrote: >I'm not talking about calculations just about selecting the actual size of >the pipe. Should I use a 1" pipe on 2 sprinklers or use a 1" pipe as long as >the gpms are less than 10. I just want to know how people know or choose the >size of pipe they use for each branch, sprig and main. > >Karen Purvis >Senior Designer >Facility Systems Consultants >713 South Central Street, >Suite 101 >Knoxville, TN 37902 >ph.865-246-0164 >fax 865-246-1084 > >-----Original Message----- >From: [email protected] >[mailto:[email protected]] On Behalf Of Matt Grise >Sent: Wednesday, February 10, 2010 4:23 PM >To: '[email protected]' >Subject: RE: pipe sizing question > >In some of the jurisdictions around here the AHJ's do allow submittals >without calcs for small add/relocate, and tenant improvement work as long as >it does not exceed the original hydraulic design of the shell system >(adjusting an OH2 retail system to accommodate a LH office, etc). > >I am familiar with the pipe drop charts you are talking about. The main >issue I see with those is that it could be difficult to account for >over-flow at each head, so you could end up with more water flowing than you >anticipate. > >Matt Grisé PE*, LEED AP >Sales Engineer >Alliance Fire Protection >*Licensed in KS & MO > >913.888.0647 ph >913.888.0618 f >913.927.0222 cell >www. AFPsprink.com > > >-----Original Message----- >From: [email protected] >[mailto:[email protected]] On Behalf Of Travis Mack, >SET >Sent: Wednesday, February 10, 2010 3:18 PM >To: [email protected] >Subject: Re: pipe sizing question > >It is my understanding that you need to provide calculations per NFPA >13, or use the pipe schedule method where it is allowed. You can >estimate with tables showing pressure drops, but that likely won't >suffice for submittal to the local authorities in any where that I have >done work. > >On 2/10/2010 2:08 PM, Karen Purvis wrote: > > We mainly do new and add-on systems a few retrofits no grids no high piled > > storage no extra hazard. Usually all light and ordinary hazard. > > > > Karen Purvis > > Senior Designer > > Facility Systems Consultants > > 713 South Central Street, > > Suite 101 > > Knoxville, TN 37902 > > ph.865-246-0164 > > fax 865-246-1084 > > -----Original Message----- > > From: [email protected] > > [mailto:[email protected]] On Behalf Of > > [email protected] > > Sent: Wednesday, February 10, 2010 4:12 PM > > To: [email protected] > > Subject: RE: pipe sizing question > > > > For what kind of systems, new, retrofits, tree, grid, etc.....? > > > > > > Craig L. Prahl, CET > > Fire Protection Specialist > > Mechanical Department > > CH2MHILL > > Lockwood Greene > > 1500 International Drive > > PO Box 491, Spartanburg, SC 29304-0491 > > Direct - 864.599.4102 > > Fax - 864.599.8439 > > [email protected] > > http://www.ch2m.com > > > > > > -----Original Message----- > > From: [email protected] > > [mailto:[email protected]] On Behalf Of Karen >Purvis > > Sent: Wednesday, February 10, 2010 3:57 PM > > To: [email protected] > > Subject: pipe sizing question > > > > This may seem like a very newbie question but here goes. How do most of >you > > guys size your pipe other than using a hydraulic calculation program? I >have > > been using a pressure drop chart that list pressure drop and velocity in > > schedule 40 pipe for water at 60°F per 100 feet drop. So far this has >worked > > for me but now I have someone questioning my method. Should I be going >back > > to the pipe schedule method? > > > > > > > > Karen Purvis > > > > Senior Designer > > > > Facility Systems Consultants > > > > 713 South Central Street, > > > > Suite 101 > > > > Knoxville, TN 37902 > > > > ph.865-246-0164 > > > > fax 865-246-1084 > > > > _______________________________________________ > > Sprinklerforum mailing list > > [email protected] > > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > > > For Technical Assistance, send an email to: [email protected] > > > > To Unsubscribe, send an email to:[email protected] > > (Put the word unsubscribe in the subject field) > > _______________________________________________ > > Sprinklerforum mailing list > > [email protected] > > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > > > For Technical Assistance, send an email to: [email protected] > > > > To Unsubscribe, send an email to:[email protected] > > (Put the word unsubscribe in the subject field) > > > > _______________________________________________ > > Sprinklerforum mailing list > > [email protected] > > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > > > For Technical Assistance, send an email to: [email protected] > > > > To Unsubscribe, send an email to:[email protected] > > (Put the word unsubscribe in the subject field) > > > > >-- >Please feel free to call if you have any questions or comments. > >Sincerely, > >Travis Mack, SET >MFP Design, LLC >2508 E Lodgepole Drive >Gilbert, AZ 85298 >Office (480) 505-9271 >Fax (866) 430-6107 > >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > >For Technical Assistance, send an email to: [email protected] > >To Unsubscribe, send an email to:[email protected] >(Put the word unsubscribe in the subject field) >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > >For Technical Assistance, send an email to: [email protected] > >To Unsubscribe, send an email to:[email protected] >(Put the word unsubscribe in the subject field) > >_______________________________________________ >Sprinklerforum mailing list >[email protected] >http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > >For Technical Assistance, send an email to: [email protected] > >To Unsubscribe, send an email to:[email protected] >(Put the word unsubscribe in the subject field) Todd G. Williams, PE Fire Protection Design/Consulting Stonington, Connecticut www.fpdc.com 860.535.2080 _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
