We are in business to make money and on an issue like this we need to remember the words of our dear late friend George Church: keep it simple
Sent from my Galaxy S®III -------- Original message -------- From: "rongreenman ." <rongreen...@gmail.com> Date: 09/24/2013 9:09 PM (GMT-05:00) To: sprinklerforum@lists.firesprinkler.org Subject: Re: old 14.5k ecoh brass upright Something I've said a million times and Scan demonstrates very well with very large Italian waving arm gestures is that the calc method is a model. That all the numbers used are approximations, constants and variables, and when actually accurate either based a fixed theoretical or on a snapshot of actual performance from a test at a particular time, on a particular day, in a particular year and are supposed to apply to a system at any time, on any day, over a period of years. Add to that it's all based on a specific number of heads operating at specific locations. I would need a much more controlled environment than I can possibly have, with measuring instruments of far greater precision, using factors such as temperature and actual specific gravity of the fluid, and far more quality control at the pipe manufacturers' facilities to be able to calc something to the degree of accuracy that is sometimes suggested by forum members (and definitely often by writers on the SFPE forum). There has to be a lot of slop built into this model as it has to perform yeoman service under so many different conditions in so many differing scenarios. An example is an old Grinnell head that under flow x has a 9.0K, under y it's 9.1K, and so on in tenths increments. That would be the paragraph describing the head's characteristics. In the paragraph of how to apply it within calcs the cut-sheet said to always use 9.2K. It later became, for calculation purposes, an 8.0K head. Now nothing about the head itself changed, just how one dealt with it in a calc sheet. Easier to understand is the head that changed from quick response to standard response at a certain height from the floor. Then there's the sidewall head I wanted to use in a slight stretch of it's listing, based upon the response of similar upright/pendant head under comparable conditions. The brainiac I talked to this about at Tyco said he agreed that it should work and took it to theTyco brainiac coven where everyone peered into their crystal balls, agreed that it ought to work, and then officially said no. Wasn't listed that way, they weren't going to get it listed that way, and they certainly weren't going to stick the corporate neck across the chopping block. All very reasonable, The point being there's a lot that is subsurface on this stuff and to try to out guess the book is a waste of time. Put in reasonably good data collected in the prescribed manner, note who gave you any data that could be questionable that you weren't able to personally verify, follow the prescribed method of calcing, make no, or at least insignificant mathematical errors, be able to demonstrate your use of industry standards in your execution, and consistency of that execution over time, and you can expect good results. Every time I've ever had a problem I've found it due to something out of my control, except once when I was in a hurry and had a result that I should have just known was impossible. That and a couple times of wanting a particular solution so bad that I manipulated it enough until I was able to justify that the wrong solution that I'd come up with previously was now the right solution. This thread started out that way with I want this but this is what's happening. Happy ending though is you can have what you want but not for the wrong reason you're trying to get agreement to. On Tue, Sep 24, 2013 at 3:47 PM, Cahill, Christopher <ccah...@burnsmcd.com>wrote: > So let's say a hypothetical company (Globe) is putting out Listed 8.1 > heads? Are they acceptable per 13 to use here in NFPA 13 land and > calculate with 8.0? I know it's a nominal k and k's vary with actual > flow. But Greg started this showing a system that wouldn't work with a > k14.5 vs. 14. I also realize work and not work is theoretical and if the > valve is open nothing else matters statistically (a little hyperbole so > don't focus there). I recently told a contractor no but am second guessing > myself now. > > Chris Cahill, PE* > Senior Fire Protection Engineer > Burns & McDonnell > 8201 Norman Center Drive > Bloomington, MN 55437 > Phone: 952.656.3652 > Fax: 952.229.2923 > ccah...@burnsmcd.com > www.burnsmcd.com > > Proud to be one of FORTUNE's 100 Best Companies to Work For > *Registered in: MN > > > > > -----Original Message----- > From: sprinklerforum-boun...@lists.firesprinkler.org [mailto: > sprinklerforum-boun...@lists.firesprinkler.org] On Behalf Of Roland > Huggins > Sent: Tuesday, September 24, 2013 2:40 PM > To: sprinklerforum@lists.firesprinkler.org > Subject: Re: old 14.5k ecoh brass upright > > Now how could it be Off the record while on a public Forum - lol. Anyhow > the answer is No. Not an opinion but stated in 13. > > > Roland Huggins, PE - VP Engineering > American Fire Sprinkler Assn. --- Fire Sprinklers Saves Lives > Dallas, TX > http://www.firesprinkler.org > > > > > > On Sep 24, 2013, at 11:26 AM, Brad Casterline <bcasterl...@fsc-inc.com> > wrote: > > > Roland, > > > > Does this mean we can calc K=14.5 when using a K=14.0 head, in your > > opinion, off the record? > > > > Brad > > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > _______________________________________________ > Sprinklerforum mailing list > Sprinklerforum@lists.firesprinkler.org > > http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org > -- Ron Greenman Instructor Fire Protection Engineering Technology Bates Technical College 1101 So. Yakima Ave. Tacoma, WA 98405 rgreen...@bates.ctc.edu http://www.bates.ctc.edu/fireprotection/ 253.680.7346 253.576.9700 (cell) Member: ASEE, SFPE, ASCET, NFPA, AFSA, NFSA, AFAA, NIBS, WSAFM, WFC, WFSC They are happy men whose natures sort with their vocations. -Francis Bacon, essayist, philosopher, and statesman (1561-1626) _______________________________________________ Sprinklerforum mailing list Sprinklerforum@lists.firesprinkler.org http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org _______________________________________________ Sprinklerforum mailing list Sprinklerforum@lists.firesprinkler.org http://lists.firesprinkler.org/listinfo.cgi/sprinklerforum-firesprinkler.org
