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Posted By: C-H Leaning poles? - 01/18/05 09:13 AM
As many of you know, there was a storm last weekend in northern Europe. I just noticed that one of the largest Swedish utilities, Sydkraft, have put up some pictures on their website (www.sydkraft.se) of the work facing their linemen. The work turned out to be harder than first expected, but they nevertheless expect to have repaired the network in less than a month.

There is no comment to the pictures, but I thought some were worth posting here.

[Linked Image from sydkraft.se]
[Linked Image from sydkraft.se]
[Linked Image from sydkraft.se]
[Linked Image from sydkraft.se]
Posted By: Trumpy Re: Leaning poles? - 01/18/05 09:50 AM
C-H,
Thanks for the pictures!.
Looks like Earth faults all round!.
What voltages are involved in each of the pictures?.
One thing about being a Line Mechanic, you certainly get used to using a Chain-saw.
Remember what I was saying to you a few years back about the size of HV insulators C-H, these are small ones, but look at them in relation to the size of the guy.

[This message has been edited by Trumpy (edited 01-18-2005).]
Posted By: pauluk Re: Leaning poles? - 01/18/05 08:25 PM
Looks like you got hit pretty bad up there as well. [Linked Image]

As the second pic was loading, at first glance it looked like the jib of a crane being used to haul up a pole -- Then I realized it was actually a suspension tower. Must have been some force there for it to buckle like that.
Posted By: C-H Re: Leaning poles? - 01/28/05 10:06 AM
Mike,

the voltage is mostly 11 kV. You're darn right about the size - I didn't realise how large these things are.

The above mentioned utility is still busy fixing its network. They have close to 3000 line(s)men out and have had two fatalities in the past week. One man was killed when the pole he had climbed broke. A helper was killed when the lineman failed to check that the 11 kV line was deenergized before they commenced work. (The lineman will go to court for this: The deceased was under-age and unlicensed.)
Posted By: C-H Re: Leaning poles? - 01/28/05 11:19 AM
Mike, I bet there has been a fantastic market for chainsaws in the past weeks. They also use explosives to remove trees from power lines. I don't know how well (or even if) it works, but there is a special device for it. (http://www.explosivaumea.com/safetcut/safetcute.html)

Are any "unusual" methods of clearing the power lines used down under?
Posted By: Trumpy Re: Leaning poles? - 01/29/05 07:30 PM
Hi C-H,
Quote
Are any "unusual" methods of clearing the power lines used down under?
Not really anything unusual, is used here.
(how's that for shocking sentence structure?, I've just got out of bed) [Linked Image]
We usually use cranes and chainsaws as a rule.
That's terrible to hear about that young fella, line-work is inherently dangerous by the size of the equipment used.
More size= more force to get out of the way of.
Oddly enough C-H, just looking at some of them pictures, apart from the power pylon types, I'd swear it was rural New Zealand.
That's strange. [Linked Image]
Posted By: kiwi Re: Leaning poles? - 02/01/05 08:33 AM
looking at the pylon in pic 2, jeez, what was the wind speed during tht storm. And what would the windage rating on that particular pylon be ? It buckled like a plastic straw ! !
Posted By: Trumpy Re: Leaning poles? - 02/01/05 02:05 PM
It's sort of rather hard to gauge how big that pylon in pic No. 2 actually is, as there's nothing else in the picture to scale it against.
What size is that warning sign?.
The thing about poles and pylons in windy conditions, it's not just the wind resistance of the pole that can bend/break it, but the two spans of conductors on each side that make the pole move as the wires get pulled by the wind currents.

[This message has been edited by Trumpy (edited 02-01-2005).]
Posted By: C-H Re: Leaning poles? - 02/03/05 08:31 AM
Not sure about the voltage on the pylon. Wooden poles are used not only for 11 and 22 kV but often for higher voltages. Could be a 33 kV line, but I think Mike is much better at guessing this than me. [Linked Image]

The wind only reached speeds of 40 m/s (90 mph), a mere breeze compared to what they get in places like Florida. Of course, I don't know how windy it was where this pylon is located.
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