Ron, If this is true then why are we seeing so many systems develop holes in wet pipe schd 10 systems in 10 years and 8-10 years for dry systems with rust thru. The old schd 40 systems lasted for 60-80 years with no problems dry system less of course. Is MIC that new that it did not exist in the 1915-1950 era?
Art @ATCO -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Ron Greenman Sent: Saturday, January 26, 2008 12:07 PM To: [email protected] Subject: Re: Fire sprinkler question Tom, Metallurgy hasn't gone downhill. In fact. like almost all technologies, the improvements have been exponential in this century, that again in the last sixty years of the Twentieth, and again in the preceding one hundred. Remember that in the centuries before the Industrial Revolution mankind, whether clannish/tribal or politically organized, was essentially living in a sticks and stones technology. I would venture that the quality of materials hasn't fallen but rather that the control of the manufacturing process has improved so much that guesswork is gone and it's unnecessary to over-build as much as it used to be to meet minimum levels of quality control. The shift from pipe schedules to hydraulics is a perfect example. Confidence in the numbers allows us to design closer to the edge. Confidence in the manufacturing process allows the manufacturers to meet ASTM minimums with lighter and lighter walled products. If we find that these products fail too soon it's the standard that requires adjustment; The manufacturing process in this case has philosophically approached near perfection--as close to minimum standard as possible while maintaining quality control per that standard thus minimizing per unit costs. And before someone jumps on the emerging nation, sub-standard product bandwagon, that is a geo-political issue and not a science/manufacturing technology one.I have the technology to produce a mild steel product that meets the ASTM minimum to a +/- 0.05% tolerance and then exceed the standard for galvanizing by being able to imbed/fuse if you will the zinc/tin into several microns of the finished product rather than coat the product like paint (Idod's stuff--and if you haven't already check out their process, fascinating), either by hot dipping (thick & way expensive) or electroplating, then I can lower material costs and hence my Earth footprint while producing a superior product. If I can do that then anyone can because the technology exists. If on the other hand my infrastructure is too fragile, if patents intervene, etc. I can still use old technologies and rely on larger tolerances to maintain quality control. I could go on with this rant but I'll spare you all. On 1/26/08, Tom Duross <[EMAIL PROTECTED]> wrote: > I've tested a few pumps drawing river water in CT and RI as well as MA and > found they have domestic in them off the street by way of a manual fill and > only see river water when the pump runs. Is this like that? Plus, you > don't see as good a metal product in the past 20+ years as you see in older > systems, not just pipe but pumps as well. Metallurgy has gone downhill, > domestic forges closed, quality of ore not what it used to be. > > Tom > Go Pats > > > As another example, I am working on a mill conversion and the > building and sprinkler system are from 1904. When we changed the 3/4" > pipe, the internal looked like new pipe. This had been a wet system, > but was fed by river water. Go figure. > > > > At 07:41 PM 1/25/2008, you wrote: > >I agree Tom. Here is what I plan to respond unless I hear words of > >wisdom from you guys. > > > > > > One must accept the fact that there are variables which affect > > the life of a sprinkler system. They include: > > > > Proper original design and installation > > Proper inspection and testing > > Whether they are wet, dry, preaction or antifreeze > > Environmental conditions, like salt air, high humidity, corrosive > > atmosphere. > > Presence of microbiologically induced corrosion (MIC) > > Type of pipe, Schedule 40, thinner wall pipe, galvanized pipe, plastic > pipe > > Corrosive nature of the water > > Earthquake > > > > A new or existing wet pipe system which has been tested free of > > the conditions leading to MIC, and is properly maintained, can > > pretty much be expected to last for the life of the > > building. Examples of this are the sprinkler systems at The > > Presidio and Fort Mason in San Francisco. I know the system at the > > Headquarters Building at Upper Fort Mason is in the neighborhood of > > 70 years old. I took apart portions of another 70 year-old > > sprinkler system in San Francisco, during a building > > demolition. The exterior and interior of the pipe was like brand new. > > > > Dry pipe systems do not have such a good history, mostly because > > of internal corrosion. I know of no statistics, but would expect > > at 30 to 40 years. > > > > Antifreeze systems will not get proper maintenance, so it is > > anybody's guess. > > -- Ron Greenman at home.... _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
