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imsmooth

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Joined: 07/02/2008
Location: United States
Posts: 214

Posted: 12:54am 20 Aug 2008

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I was going through a fence companies pipe stock and want to use galvanized pipe for a guyed tower. Total height 35'. Guy locations at 15' and 30' up. Turbine diameter is 8.5 feet. Will 2" (ID) / 2.375" (OD) schedule 40 pipe be sufficient, or is 2.5" (ID)/2.875" (OD) pipe required for this height? I would think that if they guy cables are handling the thrust forces then the 2" should work.

Any comments?Edited by imsmooth 2008-08-21

KiwiJohn
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Joined: 01/12/2005
Location: New Zealand
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Posted: 01:26am 20 Aug 2008

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I imagine guyed towers are a bit of a science and I dont think you have enough guys.

Considering that the main horizontal load will be at the top of the mast which is 5 feet above your guys I think the mast will tend to buckle out at 5 feet below the guys which is 10 feet above your next guys.

Just my thoughts.

dwyer
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Joined: 19/09/2005
Location: Australia
Posts: 574

Posted: 09:14am 20 Aug 2008

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Hi imsmooth
Just be aware of any galvanized pipe buy from hareware shop or fence companies are design for water pipe, normal fence height as galvanized pipe are not very strong

as you think so best to go and see suppliers of metal product or steel fabication company In Ausralia steel company sell diffrent grade materail strenght of steel
for sample normal galvanized pipe grade 250 is very soft use for fences, handrail,water pipe ,letterbox post, road sign etc, next one up is 350 sighting better,450 is stronger,so on high pressure pipe is the best in strengh will cost you double $$$ or more so best see someone who know in the steel industries first before you buy

Dwyer the bushman

GWatPE

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Joined: 01/09/2006
Location: Australia
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Posted: 09:25am 20 Aug 2008

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Hi imsmooth,

be sure as the wind blows that the 2" pipe will bend and probably wreck your mill. On that size mill, 3", or more would be a better size of the higher grade steel.

Gordon.

BTW my tower is 100mm and is only 7m high, with 3 guys.Edited by GWatPE 2008-08-21

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Gizmo

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Joined: 05/06/2004
Location: Australia
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Posted: 11:28am 20 Aug 2008

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I agree, the bigger the better, and 2inch isn't big enough.

My tower is about 7 meters (23 foot) tall, with 8 guy wires, and I'm using 75mm (3 inch) pipe. Th reason I chose 3 inch pipe is because I know I DONT know enough about guyed towers to build one with 2 inch pipe.

Bigger pipe is more expensive, but not my much compared to the peace of mind it buys.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
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oztules

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Joined: 26/07/2007
Location: Australia
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Posted: 11:41am 20 Aug 2008

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I know even less and am going to use 7"x 1/8" wall high tensile pipe off a big traveling irrigator... galvanised and no rust 12m lengths.... I'm a sook and am only using 1 x 12m length.

.........oztules

Village idiot...or... just another hack out of his depth

dwyer
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Posted: 12:30pm 20 Aug 2008

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Oztules
I do know the 7'x1/8' wall high tensile pipe same as you have as i brought it four years ago from scrap metal (reject) 6 off nothing much wrong with it unfortuly l cut it up to use for farm fences around my property and 8 post front main enter on my driveway but they are bloody tough steel but l didn't save one for my future mill

dwyer the bushman

oztules

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Joined: 26/07/2007
Location: Australia
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Posted: 08:19pm 20 Aug 2008

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says it all Dwyer. 7 inch pipe doesn't grow on trees.

ouch

..........oztules

Village idiot...or... just another hack out of his depth

Robb
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Joined: 01/08/2007
Location: Australia
Posts: 221

Posted: 02:53am 21 Aug 2008

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oztules said I know even less and am going to use 7"x 1/8" wall high tensile pipe off a big traveling irrigator... galvanised and no rust 12m lengths.... I'm a sook and am only using 1 x 12m length.

.........oztules

Darn lucky you have a bulldozer available. Hope you have real strong cable and Gin pole.

Are you planing to mount the mill on the ground or take it up in bits and build it up top?

GWatPE

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Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 04:27am 21 Aug 2008

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I have seen a ginpole rig, 20m pole 6" bore casing, 8 guys, Skystream3.7 downwind mill on top. Maintenance could be 1 person with a TURFER. 10m Ginpole.

Gordon.

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oztules

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Joined: 26/07/2007
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Posted: 05:07am 21 Aug 2008

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Hi Robb
Yep she's a fair lump of pole. The thought of me suspended 12m above the ground, grappling with a big turbine,.... just doesn't do it for me.

No as Gordon says, I will be using a ginpole... probably 6m long, so it will be a doddle to get it up....... he said

Village idiot...or... just another hack out of his depth

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