Sigh. You guys ever cover Areva for a few days? Ever SEE a SG? Talk for a few hours while they run probes with the engineers on the headphones and you learn. Why the sarcasm? Mean people.
High seismic + very large SG (2 loop 1150 MW CE) = lots more stabilizers, retaining bars, retainers, egg crates to immobilize longer tubes. Smaller 4 loop SGs in Nebraska get much less steel.
Tube issues not due to corrosion. Problem is wear at certain very specific points where civil structures are rubbing tubes. Design issue - engrs talk about being related to very large SGs, lots of retainers, massive flow. Hard to model perfectly, so something vibrates a little, tubes rub, wear in spots. Not at all unusual, although disappointing.
Plug affected tubes. Pass costs back to Mitsubishi. Eddy current test again next outage to verify nothing else rubbing. Biggest headache from the whole experience: list sarcasm.
Did the old S/G's - which were EXACTLY as large as these - leak right after they were installed?
Have bigger S/G's than these leaked right out of the box?
If you bought as new Ford F450 pickup truck, and it blew a head gasket a month off the dealer's lot, would you accept a BS explanation like this one that you seem to be so willing to accept here? "Oh, it's a big truck so you can't expect it to last ..." CRAP.
Again: there are only TWO possible reasons why these things are leaking as they are.
1. There was a flaw in the design/and or manufacture, making them damaged goods from the start.
2. They were operated outside their design parameters.
Nobody really wants to hear the excuses that you are parroting here. If it is so damned difficult to design and build larger boilers so that they don't leak, then you work harder, think smarter, or leave it to the people who know what the hell they are doing!
This IS NOT a freakin' pickup truck. It is a nuclear power plant fercryinoutloud! You really need to wrap your head around the fact that this $h!t is important!!! So, you "covered Areva for a few days", that hardly makes you an expert, and I don't think there is a Holiday Inn Express anywhere nearby. But, you don't need to be an expert, or a genius.
Even a blockheaded HP tech who thinks that watching some other people do work makes him knowlegeable about what they are doing has to understand that excuses are no substitute for performance, and the public will not long tolerate a nuclear plant that operates on the principle that an apology and an excuse is a sufficient substitute for safe and reliable operation.