We installed a pump due to a degraded water supply at a facility where there'd been a variety of contractors installing systems. In determining the demand for the existing system, we were amazed at the number of errors in the calcs by others. On one we opened up three more heads in a 1500 SF MRA compared to what passed muster previously. Don't know if they closed them to stay under the original supply without a pump, or they just never bothered to learn & apply the rules. Good thing there's all that fat in the rules and regulations on sprinklers or half the sprinklered buildings would burn when they catch fire. Seriously, that additional water from the initially higher than needed static pressure on the first heads likely does a lot for controlling the fire in initial stage.
George Church' Rowe Sprinkler [email protected] 570-837-7647 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of ParsleyConsulting Sent: Thursday, December 16, 2010 4:53 PM To: [email protected] Subject: Re: 0.58 over 2000 Bill, I don't think you're crazy at all. I've seen any number of submittals with similar results. Some of the reasons I've noted are: *failure to check SxL=AxD=Q for each flowing sprinkler to verify demand *failure to properly draw the remote area, any boundary past halfway between sprinklers must extend to the next sprinkler *failure to calculate the minimum number of sprinklers on a branch correctly *closed sprinklers in the calculations which should be flowing [my personal favorite] food for thought, PARSLEY CONSULTING Ken Wagoner, SET 760.745.6181 voice 760.745.0537 fax [email protected] <mailto:[email protected]>e-mail www.ParsleyConsulting.com <http://www.ParsleyConsulting.com>website On 12/16/2010 1:23 PM, Bill Brooks wrote: > Reviewing a hydraulic calc for a 0.58 over 2000 gridded warehouse system. > All seemed OK until I reached the BOR flow of 1143 gpm. From this I > assume the selected design area isn't correct since there's no way a > 0.58 over 2000 system should flow less than 1160 gpm. I've never > heard of hydraulic imbalance that results in lower overall flow. Am I > crazy or is there a new version of sprinkler hydraulics out there? > > Bill Brooks > > William N. Brooks, P.E. > Brooks Fire Protection Engineering Inc. > > > _______________________________________________ > 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)
