In current foam design, the concentrate is only in concentrate form at the exit of the bladder tank as it is introduced into the system piping at the proprtioner. From that point on it's only at typically 3% in concentration with water. So Frans I'm not sure what kind of systems you are describing because most are dry or pre-action when talking about the majority of systems. No need for stainless pipe, welded fittings or flanges for systems which will be dry most of their lifetime. Now the concentrate piping between the bladder tank and proprtioner is typically stainless and threaded. But beyond that, the systems follow NFPA 13 or 15 for installation standrds for the most part.
CH2MHILL/SPB Craig Prahl 8640599-4102 ________________________________________ From: [email protected] [[email protected]] On Behalf Of Frans Stoop [[email protected]] Sent: Saturday, April 17, 2010 3:04 PM To: [email protected] Subject: RE: Foam system piping Russell, The problem with foam concentrate is that it always tends to creep out of the piping and equipment, passing along seals, fitting threads etc. This behavior is caused by its zero surface tension. To keep it in the piping as much as possible we usually specify welded pipe connections or connections with positive pression on the seals only, like flanges. Groove couplings are to be avoided. Threaded fittings to be fitted with hard sealing Loctite and for diameters not exceeding 1 inch only. And the stuff still keeps creeping out along valve stems etc. Small foam concentrate spills and leaked droplets on the outside of pipe and equipment dry out and become a thick and corrosive salt-solution. After a few years this wet salt is able to erode all kinds of paint (including epoxy paint!), ordinary steel and cast iron. For aircraft hangars we use to design and specify for a lifetime of 25 years. According to our experience only stainless steel piping and stainless steel or chrome plated bronze valves survive that lifetime when in direct contact with foam concentrate. Concentrate spills are easily wiped or washed off with a cloth, even after a year or more, and the system keeps looking good. Yours sincerely, Frans Stoop TOS architecture & fire protection Netherlands <[email protected]> Tel. +31-24-324 0112 At 16:53 14-4-2010 -0400, you wrote: >A very, very large airport terminal. Not military. > >Russell Rewis >Brown Automatic Sprinklers, Inc. >107C Hemlock Street >Valdosta, Georgia 31601 >229-244-8130 >[email protected] >-----Original Message----- >From: [email protected] >[mailto:[email protected]] On Behalf Of >[email protected] >Sent: Wednesday, April 14, 2010 4:41 PM >To: [email protected] >Subject: RE: Foam system piping > >So what's the application is we may ask? Just curious? _______________________________________________ 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)
