I read with interest of your pvc problems, as I have had a 4" line running almost 700 feet down the hill for the last 5 years with no problems so far (knock on wood now that I have said the words) we have lots of deer in the yard and the usual varmets....hope my luck holds out!!
doug ----- Original Message ----- From: "Lewis" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, July 16, 2004 9:38 PM Subject: [microhydro] Re: penstock material questions > Hello, > > Be very wary of bursting pressure. It is one of those numbers that > can be manipulated to mean anything. > C900 comes in working pressure ratings of 100, 150, & 200 psi. These > are the only numbers you should consider. Now, according to my very > rough calculations, you should have about 300 psi working pressure at > the bottom of your run. That pretty much elimates C900 for your > situation. And, don't forget about surge pressures, which can be 3 > times your working pressure. > Also, I have found 2 problems with using pvc, but that doesn't deter > my using it in some cases. 1) Deer love to poke their hoofs thru it. > 2) Rodents love to chew holes in it. > Now, if you can find a work around to those two problems, or you are > willing to live with occasionally having to replace sections of the > run, then go ahead and use it. > > Just my 2 cents worth, > > Lewis Hughes > Hughes Micro Corp. > > > --- In [EMAIL PROTECTED], "Eric Youngren" <[EMAIL PROTECTED]> wrote: > > Hi folks, > > > > Well I'm finally getting to the point where I'm ready to place my > orders for pipe and fittings for my high-head penstock. > > > > I've been talking with different pipe suppliers and getting a lot of > different, and contradictory, information about the pros and cons of > various materials. I thought maybe I'd throw it out there to the list > to see what y'all suggest. > > > > Here's the pipeline details: > > Gross head : 650 feet > > Design Flow : 200 gpm (varies from 50 - 350 gpm seasonally) > > Penstock length : 1500' > > Site: Very steep and rugged, forested w/ exposed bedrock in many > places, some loose shale > > > > Based on those parameters we're going to use 4" diameter pipe. I > have been thinking of using 160 psi rated HDPE for the first 500' of > length because it is relatively easy to install and very durable over > time. Below the poly I'll need higher pressure rated pipe. My first > thought is steel, using Victaulic couplers to connect the 21' > sections. But steel is now close to $5 per foot and I'm not looking > forward to hauling all of that heavy pipe up and down the mountain all > summer, and steel will eventually rust. I talked to a supplier this > morning who highly recommended C900 PVC. It is a bit lighter than > steel, rated for 985 psi bursting pressure, and half the price of > steel. He also assured me that it is UV stable, impact resistant and > will last longer than steel. Another guy I talked to was suggesting > ductile iron pipe, which I know little about so far. > > > > So those seem like my options, steel w/ external couplers, C900 PVC > or ductile iron. What do you think? I'm no engineer so I'd love to > hear from anybody who sees any obvious or not-so-obvious advantages to > one of these materials. > > > > Thanks, > > Eric > > > > > > [Non-text portions of this message have been removed] > > > > > > Does your company feature in the microhydro business directory at http://microhydropower.net/directory ? If not, please register free of charge and be exposed to the microhydro community world wide! > > NOTE: The advertisements in this email are added by Yahoogroups who provides us with free email group services. The microhydro-group does not endorse products or support the advertisements in any way. > > More information on micro hydropower at http://microhydropower.net > > To unsubscribe: send empty message to [EMAIL PROTECTED] > Yahoo! Groups Links > > > > > > ------------------------ Yahoo! Groups Sponsor --------------------~--> Yahoo! Domains - Claim yours for only $14.70 http://us.click.yahoo.com/Z1wmxD/DREIAA/yQLSAA/FGYolB/TM --------------------------------------------------------------------~-> Does your company feature in the microhydro business directory at http://microhydropower.net/directory ? If not, please register free of charge and be exposed to the microhydro community world wide! NOTE: The advertisements in this email are added by Yahoogroups who provides us with free email group services. The microhydro-group does not endorse products or support the advertisements in any way. More information on micro hydropower at http://microhydropower.net To unsubscribe: send empty message to [EMAIL PROTECTED] Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/microhydro/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
