Would it be possible to heat trace the areas where you need pendants and use high pressure standard heads?
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 David de Vries Sent: Thursday, November 11, 2010 6:21 PM To: [email protected] Subject: RE: High Pressure Dry Pendents Matt, I liked your idea. That is the way I designed the system to begin with. Then the shops came in without the PRV, with a high pressure DPV and high pressure uprights on most of the system. Just a handful of dry pendents, but the cut sheet says 175 max. And I have found none listed for the 215 static wet pressure. So we might end up cutting in a PRV. Yes, George and Thom, I know it will only see about 50 most of the time and may not see the full 215 even when the DPV trips. Although wet sprinklers are tested at 500 psi (for a few seconds) and so says the cut sheet, the dry sprinkler cut sheet does not say that. Are they also tested at 500? The cut sheet says tested pneumatically at 100. Makes me think the procedure is not the same and the dry sprinklers are not quite so robust as the wet ones. Chris, we are designing to avoid the false trip from a dead compressor (supervised low air), but maybe a little hammer from the fire pump starting from a dead jockey pump will trip the DPV. Then you are right; we get the full static pressure. Ron, if the dry pendents could take 225 or 250, why is no mfr listing them for that pressure? Sure, there is a cost, but it seems there would be applications for them and a competitive advantage to the mfr (at least the first one!) who does list them at high pressure. Craig, all the system components are listed for 250 or 300, except the dry sprinklers. Lastly, the mfr's senior tech services mgr says 175 rated sprinklers are "not recommended for this application". And, "the hydrostatic test pressure should not exceed 225." So, no one knows of a high pressure dry pendent ... even an ugly one?? Dave David A. de Vries, P.E., CSP Firetech Engineering Incorporated 2715 Harrison St. Evanston, IL 60201 Tel: 847-733-0944 Fax: 847-866-6255 --- On Thu, 11/11/10, Matt Grise <[email protected]> wrote: From: Matt Grise <[email protected]> Subject: RE: High Pressure Dry Pendents To: "'[email protected]'" <[email protected]> Date: Thursday, November 11, 2010, 3:57 PM Nobody liked the pressure reducing valve? What if you put it in front of the dry pipe valve? 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 [email protected] Sent: Thursday, November 11, 2010 3:44 PM To: [email protected] Subject: RE: High Pressure Dry Pendents Is all the piping, fittings, etc., rated for 300 psi? If you're worried about the heads, don't forget the whole system is technically rated for 175. Craig Prahl CH2MHILL/SPB 864-599-4102 ________________________________________ From: [email protected] [[email protected]] On Behalf Of David de Vries [[email protected]] Sent: Wednesday, November 10, 2010 11:42 PM To: AFSA SprinklerForum Subject: High Pressure Dry Pendents I have an open parking garage under a high rise. Fire pump sized for standpipe demand, so it has over 200 psi at the garage level. Most of the dry pipe system in the garage has uprights, but there are some finished ceiling areas that need dry pendents. I have not found any dry pendents listed for more than 175. Suggestions? Of course, for most of the time the system will only see the ~50 psi air, but when the valve trips, it will be about 215. Am I wrong to think the DP's should be listed for the static system pressure? Dave David A. de Vries, P.E., CSP Firetech Engineering Incorporated --- On Wed, 11/10/10, Coastal <[email protected]> wrote: From: Coastal <[email protected]> Subject: Re: Pipe Expansion To: "Fletcher, Ron" <[email protected]> Date: Wednesday, November 10, 2010, 6:41 PM Hello Ron, It is not a building, Wooden walkway to a floating dock. Wednesday, November 10, 2010, 5:16:36 PM, you wrote: > Since the building and the sprinkler system are subject to the same > ambient conditions wouldn't the expansion rates kind of offset each > other? > Ron Fletcher > Aero Automatic > Phoenix, AZ > -----Original Message----- > From: [email protected] > [mailto:[email protected]] On Behalf Of Thom > Sent: Wednesday, November 10, 2010 3:04 PM > To: [email protected]; [email protected] > Subject: RE: Pipe Expansion > Also remember that a simple change in direction can provide the same > protection as a full expansion loop. > Subject: Re: Pipe Expansion > The expansion is the expansion no matter what fittings are employed, > well on > unrestrained steel. A fitting does not in itself restrain the pipe. > Either > the pipe moves or the want to move is translated into some internal > force. > The effect of the expansion it dependent on the fittings and the > restraintment. > _______________________________________________ > 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) -- Best regards, Charles Thurston Coastal Fire Protection Coastal mailto:[email protected] _______________________________________________ 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) _______________________________________________ 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)
