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-   -   Subterranean Power Line Blues (http://cellar.org/showthread.php?t=34810)

xoxoxoBruce 01-13-2020 11:41 PM

Subterranean Power Line Blues
 
We were talking about the CA fires and power shutdowns during those fires because of the Power Companies declared liable for $millions in damages after some of their high tension lines were blamed for starting some fires. One solution would be to bury the power lines but as the carrying capacity goes up so does the difficulty and expense. This story involves the repair of one of the really big main cables coming out of a generation station. Worst case example if you will.

Quote:

It turns out they have a problem with an underground wire. Not just any wire but a 230 KV, many-hundred-amp, 10 mile long coax cable. It shorted out. (Lotta watts!) It feeds (fed) power from the Scattergood Steam Plant in El Segundo to a distribution center near Bundy and S.M. Blvd.

To complicate matters the cable consists of a copper center conductor living inside a 16 inch diameter pipe filled with a pressurized oil dielectric. Hundreds of thousands of gallons live in the entire length of pipe. Finding the fault was hard enough. But having found it they still have a serious problem. They can't afford to drain the whole pipeline - the old oil (contaminated by temporary storage) would have to be disposed of and replaced with new (pure) stuff which they claim takes months to order (in that volume). The cost of oil replacement would be gigantic given that it is special stuff. They also claimed the down time is costing the costing LA $13,000 per hour. How to fix it and fast?

That's where the LN-2 comes in. An elegant solution if you ask me. They dig holes on both sides (20-30 feet each way) of the fault, wrap the pipe with giant (asbestos-looking) blankets filled with all kind of tubes and wires, feed LN-2 through the tubes, and *freeze* the oil. Viola! Programmable plugs! The faulty section is drained, sliced, the bad stuff removed, replaced, welded back together, topped off, and the plugs are thawed. I was amazed.
At the Boardman, OR, generation plant the connection closet(size of my bedroom) is where the feeds from the generator connect to the 500,000 volt power lines going out. There was instead of a door a steel plate with half inch bolts every two inches around the perimeter. Somebody screwed up on syncing the phase of the generator to the power line and the explosion blew that steel plate 50 feet. Nothing to fool around with, but I digress. :blush:

You can read the details of the three month repair of that CA main here. It's a good read, not real technical.

Griff 01-14-2020 06:22 AM

Again smrt. I wonder how toxic that oil is when it breaches completely?

xoxoxoBruce 01-14-2020 10:35 AM

I assume it's the same oil they use in transformers and that's nasty shit, mineral oils or more recently PCBs. :yelsick:

Gravdigr 01-14-2020 03:32 PM

Quote:

This message has been deleted by Luce. Reason: More or less repeated Bruce.
Just don't look in the mirror and repeat Bruce three times.:eek:

Luce 01-14-2020 03:34 PM

Quote:

Originally Posted by Gravdigr (Post 1044672)
Just don't look in the mirror and repeat Bruce three times.:eek:

How about I sandwich two mirrors facing in, with a ear bud in between that repeats Bruce three times?

Then we can all sit back and watch you kick your own ass.

Luce,
Always wanted to correct horror films.

Gravdigr 01-14-2020 10:06 PM

Yeah, no, I ain't trying to kick m'own ass.

Too much work.

Hard work.:cool:

Undertoad 01-14-2020 10:36 PM

Why does it have to be fighting?

Is it gay if you're, you know, fucking your actual own self?

BigV 01-14-2020 11:01 PM

There's *always* a fight.

xoxoxoBruce 01-14-2020 11:08 PM

Quote:

Originally Posted by Undertoad (Post 1044709)
Why does it have to be fighting?

Is it gay if you're, you know, fucking your actual own self?

Gay? I thought that would be like the ultimate masturbation. But except for figuratively, for me it's a moot point anyway. :blush:

tw 01-14-2020 11:40 PM

Quote:

Originally Posted by Griff (Post 1044640)
Again smrt. I wonder how toxic that oil is when it breaches completely?

Age of that cable put is before PCBs were banned for being carcinogenic.

Such cables no longer use oil. Cables for that voltage are even routinely buried in the ocean floor. One was discussed here long ago was from Connecticut to Long Island. It was incorrectly installed because it was not properly buried underneath the Sound.

Others carry power from off shore wind generators. The science has come a long way from those 'olden days'.

xoxoxoBruce 01-15-2020 01:44 AM

This happened 17 years ago, the cable was installed 34 years ago, not under water, 10 miles of dry ground just south of the LAX in Los Angeles County, CA.

tw 01-15-2020 11:46 AM

Quote:

Originally Posted by xoxoxoBruce (Post 1044721)
This happened 17 years ago, the cable was installed 34 years ago, not under water, 10 miles of dry ground just south of the LAX in Los Angeles County, CA.

Exactly the point. That cable, even then, was obsolete technology. Today, same high voltage cables are laid even under the ocean. Obviously that could not happen with pipes containing oil.

Such cables no longer use oil. Or steel pipes. Routinely and safely, power cables are buried without metal pipes or oils - on dry land and in oceans. While fears remain to entrench denials, technology has long since moved on.

Burying a high voltage transmission cable is much easier than pipelines for oil, water, natural gas, etc. Even when equipment did not exist, the Big Inch pipeline (24" diameter) was buried from Texas to Pennsylvania in only six months.

Instead we waste that money and more on a $3trillion war to waste 5000 American lives for no purpose. And were only ten minutes away from doing it again. Amazing how fear and ignorance fails to target relevant objectives.

Amazing how many love to waste money on wars. And then deny how easily wires can be buried.

That was a 230,000 volt cable. The transmission lines that probably caused CA fire would have been maybe 33,000 volt wires - or less. Easily and routinely buried even in 1970.

Of course we cannot really blame the electric companies. Since so many 'powers that be' have been denying global warming. And obstructed anything that might address that reality.

Gravdigr 01-15-2020 01:17 PM

Quote:

Originally Posted by Undertoad (Post 1044709)
Why does it have to be fighting?

Quote:

Originally Posted by BigV (Post 1044716)
There's *always* a fight.

I'm still tryin' to figger out why it's my ass that's gotta be kicked...:(

BigV 01-16-2020 02:14 PM

Quote:

Originally Posted by Gravdigr (Post 1044750)
I'm still tryin' to figger out why it's my ass that's gotta be kicked...:(

There's always a fight.

Luce 01-21-2020 11:09 AM

Quote:

Originally Posted by Undertoad (Post 1044709)
Why does it have to be fighting?

Is it gay if you're, you know, fucking your actual own self?

Me and me would never get out of the shower.

Hamish,
I'm sexy and I know it.


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