Robatoy wrote:
....

...They have tried super-
critical systems, but the plumbing had to be sooo huge as to be cost
prohibitive, like a steam line with 12" ID and 36" OD, ...

I never did find the eng'g drawings online for Bull Run and my TN
buddies are busy and I told 'em to not waste their time if didn't either
know it or have it directly at hand...

So, I did a very rudimentary minimum wall thickness calculation for
seamless tubing based on the ASME B31.1 criterion based on allowable
stress and got a number otoo 4" for 30" nominal diameter, 3500 psi
working pressure w/ steel derated to 12000 psi for temperature. I don't
think that's _way_ out of line, but it's certainly not a design
calculation.

Higher tensile strength values would reduce that at about an 80%
proportionally to the ratio of strengths. I didn'tfind the applicable
ASME table for temperature factors online and it's one I don't have at
hand (I'm a nuc-e, not mech, ... need cross-sections? I got those or
shielding data or ... ) so reduced another 20% based on a
subcritical system calculation. OTOH, one might reasonably expect
better alloys which would be higher at temperature, to compensate. So,
as is it's a guesstimate. Better data would be nice but only tables
and/or piping calculators I found were all for purchase, none were
online modules like the sagulator the likes of which I was hoping I
might find...

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