Japan Earthquake

Japan Earthquake | Page 2397

@lillymunster tx, okay, that's what i thought. i have always asked myself if the room under the rpv is closed.
by Edano 9/23/2011 11:42:04 PM

so they don't think there is a possibility to reach the torus region ?
by Edano 9/23/2011 11:44:02 PM

@lillymunster that picture is disturbing I thought it was a phallix
by elainekirk 9/23/2011 11:44:05 PM

@Edano but of course it does I am a disturbed person
by elainekirk 9/23/2011 11:45:56 PM

lilly posted this schema showing the concrete ring that the RPV+skirt sits on. media.photobucket.com
by Peter 9/23/2011 11:46:33 PM

Maybe now it will show. img.photobucket.com
by Peter via Img.photobucket 9/23/2011 11:47:58 PM

RT is currently showing a program about nuclear reactors which they claim can never melt rt.com
by wrshpr 9/23/2011 11:48:00 PM

Oh lookie - Pedestal door opening farm3.static.flickr.com
by lillymunster via Farm3.static.flickr 9/23/2011 11:48:52 PM

It does not show the maintenance entrance to the rod drives though.
by Peter 9/23/2011 11:50:01 PM

that is the Parr research reactor, not a BWR
by lillymunster 9/23/2011 11:50:38 PM

RT @SimplyInfo1: Scottish and Southern Energy said it has pulled out of its UK #nuclear new build consortium bit.ly #scotland nuclear
by elainekirk 9/23/2011 11:52:07 PM

www.tepco.co.jp
unit 5 not much use but...
by elainekirk via Tepco.co.jp 9/24/2011 12:02:41 AM

@lillymunster , as to the gap between the steel shell and the concrete shell surrounding drywells, I understand most possess this gap to accomodate steel expansion. In some the gap is stuffed with some insulation material. Check the middle of the first paragraph on page 9 here (doesn't want to copy/paste): www-pub.iaea.org

by Peter 9/24/2011 12:16:06 AM

OT
there is a diagram of #1 water level guages here if it is any use www.tepco.co.jp
by elainekirk 9/24/2011 12:17:38 AM

www.tepco.co.jp
OT again - position of all temp guages
by elainekirk 9/24/2011 12:21:50 AM

could the #2 torus explosion been caused by a steam explosion with pedestal failure in the pedestal region by quenching corium ? before the explosion, water was injected into the drywell.
by Edano 9/24/2011 12:33:37 AM

there are measurement of containment /pressure vessels / etc here ie - #1 rpv inner diameter 4.8 height 20 weight 440 etc etc etc www.tepco.co.jp
by elainekirk 9/24/2011 12:42:28 AM

"4.6.4.5 Missile Generation
Missiles may be generated when combustion (deflagration or detonation) occurs in a confined region or when a propagating combustion front produces dynamic pressure loads on equipment. Such missiles may pose a threat to the containment structure itself, as well as representing a potential threat to safety and control equipment. For instance, electrical cables may not be expected to withstand the impact of a door or metal box. The actual risk to plant safety posed by missiles generated from hydrogen combustion depends upon a number of independent factors and is very difficult to predict." (regarding #3)
by Edano 9/24/2011 12:45:10 AM

4.7.6 Potential for Mark I Containment Failure
The Mark I liner failure study has considered the case of debris release via penetration failures from a depressurized Peach Bottom reactor vessel. The study concludes that there is a "virtual certainty" of shell failure if the containment floor is dry at the time of initial release, but that early shell failure is "physically unreasonable" if the drywell is flooded with water to the lower lip of the vent pipe openings, a depth of about 61 cm (2 ft.).
For its consideration of this issue, the Advisory Committee on Reactor Safeguards (ACRS) has stated that "Results of the severe accident research have shown that there is no threat of prompt containment failure posed by ... Mark I liner meltthrough. Research should continue to: ... determine the impact of ex-vessel steam explosions on the BWR containments."'
Apparently this statement is intended to include only cases with water overlying the drywell floor.
by Edano 9/24/2011 12:50:24 AM

has the drywell been flooded in the reactors ???
by Edano 9/24/2011 12:51:40 AM

4.7.6.2 Drywell Flooding Capabilities
If the drywell floor is to be reliably flooded under severe accident conditions, then the necessary water would have to be capable of delivery into the containment in case of station blackout. The general concept is to vent the containment to permit use of low-pressure pumps and to inject the water via the existing drywell spray headers. To address station blackout concerns, it would be necessary to invoke new or upgraded independently powered pumping systems.
by Edano 9/24/2011 12:52:24 AM

@elainekirk i think they had no electricity to pump water in (at least in #1 and 3).
by Edano 9/24/2011 12:53:18 AM

Provision of the necessary volume of water would require the availability of an independent containment flooding system of sufficient capacity to cover the reactor vessel bottom head before lower plenum dryout and the associated threat of penetration failures. This would in general require equipment modifications to existing plants, but similar modifications are required for flooding to protect the shell. In both cases, the drywell would have to be vented during the flooding process and beyond.
by Edano 9/24/2011 12:55:47 AM

www.animatedsoftware.com MY GIFT TO EVERYONE.... hope this is fun
by dean 9/24/2011 12:59:34 AM

@ Edano isn't that area in the pedistal normally dry tho
by dean 9/24/2011 12:59:48 AM

even has a flow path where you can hit go.. and start the reactor and then stop
by dean 9/24/2011 12:59:57 AM

@dean they say that flooding of the drywell bottom is necessary to prevent containment failure by corium.
by Edano 9/24/2011 1:01:48 AM

but i don't think they were able to do that (maybe in #2 it was possible).
by Edano 9/24/2011 1:02:41 AM

FUKU was a HOT CORE melt ,, worst case situation too
by dean 9/24/2011 1:05:38 AM

I think with the power loss and the tsunami that they didn't get it done by their efforts but maybe the EQ resulated in some leakage of water into that area
by dean 9/24/2011 1:05:40 AM