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Posted By: Admin Steam Line Rupture at Power Plant - 08/17/03 03:37 AM
These pictures were forwarded to me with the following short explanation:
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The photos show a pipe failure in a fossil plant hot reheat steam line. The hot reheat line is the line that passes steam back to the turbine after its first pass through the turbine and return to the boiler for additional heat. The pressure in this line is significantly reduced from main steam pressures (possibly 700 psi, down from 2500 psi) as much of the steam energy has been used in the high pressure stages of the turbine. Reheat steam temperature is about 1000 degrees F, the same as main steam.
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[This message has been edited by Webmaster (edited 08-16-2003).]
Posted By: Admin Re: Steam Line Rupture at Power Plant - 08/17/03 03:38 AM
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Piece of pipe traveled over Admin Building an estimated 400+ yards, before hitting and bringing down two (2) 345 kV transmission lines and falling in parking lot.
Posted By: ThinkGood Re: Steam Line Rupture at Power Plant - 08/17/03 03:55 AM
OUCH!

Was anybody hurt?

When those 345 kV lines come down, what happens? (I mean, do they dance around sparking, do they just burn up, etc?)

That poor truck...

P. S. Photo #6, there is a fire hydrant with some other smaller hydrants (?) near it. That thing doesn't output water at an electric power plant does it?
Posted By: Trumpy Re: Steam Line Rupture at Power Plant - 08/17/03 08:03 AM
Guys,
Not sure if you are aware, but this stuff is what is known as Super-heated Steam.
A break in a line like this is hazardous because of the High Pressure and the sheer High Temperatures used with this sort of Steam.
My Father is an Engineer that works with this sort of gear everyday(Not Line-Breaks, this left to the Fire Service).
One thing you must remember about Super-Heated Steam, is the fact that it will "cut" limbs that are exposed to a direct stream of it!, I'm not joking either!. [Linked Image]
Posted By: wa2ise Re: Steam Line Rupture at Power Plant - 08/17/03 11:56 PM
I've heard about a local power plant that used to use a mix of steam and mercury. I don't know enough about this sort of thing to know if that makes sense or not. Also heard that it would be a nasty mess if they ever had a leak....
Posted By: CaOperator Re: Steam Line Rupture at Power Plant - 08/18/03 03:30 AM
AHA... right up my alley lol. I work in a steam plant. The fire plug in photo 6 is just that, a fire plug, but there is also a portable extinguisher someone set down next it, and an isolation valve (the tall skinny kind with a window to view an internal indicator), plus the usual collection of stanchions guarding them.

The first shot appears to just be a picture of the plant under fairly normal operation.

In the second shot I am fairly sure that there used to be siding completely across the wall there, sort of an exit wound.

The third shot shows an elbow, which most likely would have been welded at each end and that fact combined with the forces that occur when the rather large volume changes direction make this a likely point for a failure to begin.

Fourth shot, piece of the pipe literally split wide open.

Fifth shot, interior shot in the plant, damage to other lines, and lagging around them.

Sixth shot, fire hydrant and a huge piece of the pipe, notice the person standing in the background? The pipe looks to be about 36-48 inches in diameter.

The rest, you guys understand perfectly well lol. As to what would happen, lines like these at my plant anyway have relay protection, and would most likely immediately trip on phase differential.

The noise and heat would have been incredible, the volume passing through the pipe would have been about 10,000 pounds/minute/megawatt. These units look fairly large, probably in the 125 MW range.

I fervantly hope nobody was close by when it let loose.
Posted By: Trainwire Re: Steam Line Rupture at Power Plant - 08/20/03 01:00 PM
Notice picture 4. Imagine your in one of those johnny on the spots having a nice quiet "personal moment" while you deal with the burrito that you had last night.....

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TW
Posted By: ThinkGood Re: Steam Line Rupture at Power Plant - 08/21/03 12:25 AM
Gosh, TW, I never knew that a meal could cause such a thing:
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Piece of pipe traveled over Admin Building an estimated 400+ yards, before hitting and bringing down two (2) 345 kV transmission lines and falling in parking lot.
Posted By: Admin Re: Steam Line Rupture at Power Plant - 08/22/03 03:30 AM
Comment received via Email:
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Well well well, good pix. I worked on a nuclear power plant once, and we were working on an angle valvel in a small reheat line bypass (about 6") when the POCO plant operator cut off our lock and charged the line.

Fortunately you can hear the steam coming, my helper and I got out of the way in time, but the POCO execs getting a tour of the turbine deck got quite a show.

LOL
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