On Tue, 14 Dec 2010 19:39:47 -0800, Jon Anderson
wrote:

On 12/14/2010 3:46 PM, Jim Stewart wrote:

Early on, I tried to convince a cow-orker that a 30"
pipe pressurized to 400 psi would be quite capable
of heaving itself out of the ground and 100 feet away
just by the pressure of the gas released through a
failed weld. He wouldn't believe me....

Send him this link (fast forward to about 1:10 for the good stuff) to
see a graphic example of the power potential of compressed air or gas.

http://www.youtube.com/watch?v=xnyh7...eature=related

What percentage of that force is due to the truck rim flange and how
much is due to the jet force of a puncture? That's more of a
high-speed mechanical disconnect with mass vs a puncture.

Or would the pipeline be more of a half-circumference fracture which
enlarged? How do they actually fail? Rustouts would be pinhole jets,
but what happened here?

I dunno, but it feels like an apple/orange comparison here.

I can see that 400psi would blow out a lot of earth, but it doesn't
seem strong enough to lift a long, heavy, rigid pipe + earth unless it
had found a flame and exploded.

LJ--not an engineer.

--
Small opportunities are often the beginning of great enterprises.
-- Demosthenes