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TMI has new Steam Generators Made a big deal of delivery picture
We are only looking at 2 components here. This is a diagram showing how a nuclear plant handles ^^the heat generated in the reactor to create electricity. Fuel melting inside the reactor is caused when not enough heat is removed from the reactor core. ^^ The steam generator is the primary source of heat removal. You can think of the steam generator as a heat exchanger.
Three Mile Island’s new steam generator tubes could fail
Three Mile Island’s
New Steam Generators Could Fail
due to an unanalyzed condition.
Scott D. Portzline
The French company AREVA falsified
records and hid defects in major reactor
components it manufactured.
Areva manufactured the new Steam
Generators for TMI .
Scott D. Portzline
The Nuclear Regulatory Commission (NRC) is allowing a
major safety component (Steam Generators) at TMI to
operate with an unanalyzed condition which could
result in a catastrophic failure and lead to radioactive
The NRC is allowing licensees to swap equipment
manufactured with significant design changes, and
without extensive testing or analysis, despite a
regulation requiring proper analysis for such alterations.
TMI’s new Steam Generators have
significant design changes.
The new tube walls are only .0635 inch thick, giving them
less margin to failure than the previous design.
Steam Generator Tubes
15.597 tubes per steam generator
15.597 tubes per steam generator
These Steam Generator Tubes expand at an unexpected
rate and are made from a new metal alloy. This expansion
is causing premature wear and thinning of the tube walls.
The tubes are vibrating and banging against each other in
Under higher temperatures, as in a transient
or accident conditions, the tubes might bow
even further, and more tubes could
experience the vibrations problem to the
point of rupture failures.
Fuel melts when there is insufficient heat removal from reactor.
Steam Generators are the primary
method to remove heat from the reactor.
Steam Generator serve
critical safety functions.
• They are an integral part of the reactor coolant
pressure boundary, and thus are essential for
maintaining primary system pressure and coolant
• They also isolate the radioactive fission products in
the primary coolant from the secondary system.
• Some of the unmonitored radiation released from the
1979 TMI accident escaped through the damaged
steam generators and out of the unfiltered turbine
The Steam Generator tubes are bowing.
• The tubes bowed sufficiently far enough under normal
temperatures to cause some tubes to vibrate against
each other and cause premature wear of the tube
• Some tubes vibrated against metal plates and caused
• Under higher temperatures, as in a transient or
accident conditions, the tubes might bow even
further, and more tubes could experience the
vibrations problem to the point of rupture failures.
• A meltdown and radiological release could result.
I brought this “accident” concern
to the NRC’s attention.
• Telephone conference with the NRC, TMI, Areva
(the manufacturer) - June 17, 2013.
• On another occasion the NRC dismissed my
concerns stating – a licensee is required to be
able to mitigate the loss of a major “steam line.”
• You wouldn’t want your mechanic to
say, “We haven’t analyzed if the new
brakes will fail on a hot day, but if they
do, you have emergency brakes and can
• You want your mechanic to install brakes
that have been properly analyzed and
won’t fail under stress.
Backup plans aren’t always
what you’d think they are.
During the 1979 TMI accident, operators could not use a
backup system due to the HIGH PRESSURE.
“An auxiliary system which is designed to remove the
decay heat from the reactor was available, but it is only
operable at lower primary system pressure (<400 psi).
These attempts failed.”
Oak Ridge National Laboratories
On another occasion, about half of the
NRC staffers present agreed with me.
None of them were aware of the high
temperatures in the Steam Generators
during the 1979 accident. They had
believed that was not possible with.
• TMI openhouse April 1014.
• But nothing was ever done.
The current testing used for tube integrity does not
translate to the potential accident conditions.
The tube wear was unexpected. Therefore,
one can conclude that the testing was not
adequate even for normal conditions.
Arnie Gundersen of Fairewinds Associates
and David Lochbaum of the Union of
Concerned Scientists agree with me that the
Steam Generator design at TMI must be
properly analyzed. Both men are nuclear
The new steam generators at the San Onofre
Nuclear Plant had tube failures.
San Onofre experienced a different, yet similar problem to
TMI’s, caused by a faulty design and the NRC’s failure to
regulate. When pushed by legislators and activists, the
company chose to close the plant last year and sue the
designers of their new steam generators.
How San Onofre's new steam generators
sealed nuclear plant's fate. LA Times
“The generators that were supposed to save
San Onofre ended up killing it, and today the
atomic behemoth sits idle, never again to
produce a watt of power.”
The NRC must be made to enforce this regulation at TMI:
50.59 Changes, tests and experiments.
The Title 10 Code of Federal Regulations, Section 50.59
requirements govern design changes between original
and replacement steam generators.
A licensee shall obtain a license amendment pursuant to Sec. 50.90
prior to implementing a proposed change, test, or experiment if the
change, test, or experiment would:
(iii) Result in more than a minimal increase in the consequences of
an accident previously evaluated in the final safety analysis report
(iv) Result in more than a minimal increase in the consequences of a
malfunction of an SSC important to safety previously evaluated in
the final safety analysis report (as updated);
(vi) Create a possibility for a malfunction of an SSC important to
safety with a different result than any previously evaluated in the
final safety analysis report (as updated);
Specific regulatory sections of interest to TMI’s new steam generators: