Mitsubishi Tech Support

  • Subscribe to our RSS feed.
  • Twitter
  • StumbleUpon
  • Reddit
  • Facebook
  • Digg

Wednesday, 19 October 2011

Further test on pressure vessels at Fukushima Daiichi inconclusive

Posted on 16:05 by Unknown
Readers might recall that, earlier, TEPCO conducted tests at two of the three reactors at Fukushima Daiichi in order to attempt to determine the condition of the bottom heads of the reactor pressure vessels. In that series of tests, TEPCO attempted to test continuity in the rod position indication equipment with the hope that failed areas could be mapped by detection of failed RPI equipment. However, for one or more possible reasons the equipment was deranged enough that no meaningful data were collected. So far as this writer is aware, the test was not even conducted on No. 3 plant because the data were so nebulous on the other two.

Now, it appears that TEPCO has attempted to detect the condition of the pressure vessels at Fukushima Daiichi No. 2 and No. 3 by using sophisticated equipment to detect cable conditions in the core-contained neutron detectors.

These detectors have a continuous cable run from the equipment all the way through the reactor building and dry well (PCV) wall and to the lower head of the pressure vessel, then up to the detectors. Although TEPCO doesn't mention what was used in the tests, this author is somewhat familiar with the use of a TDR or Time Domain Reflectometer for such tests and from memory the test waveforms that TEPCO is showing appear to be the result of using a TDR on the cable runs to detect where they're open or else shorted out.

As with the previous tests using RPI cables, though, TEPCO reports that the new tests are not in any way conclusive. High temperatures and steam exposure for prolonged periods have caused the detector cables to fail such that no realistic mapping of the failed RPV regions are possible using this method.

This is the second round of testing using electric cable runs that TEPCO has attempted in its effort to diagnose the condition of the pressure vessel lower heads. As we all know too well, the condition of the lower heads is not known for certain, although surely they're expected to be found failed when finally viewed (and that first view will almost surely be remote, not the actual eyes of a man) but TEPCO feels that the earlier the actual condition is estimated or described, the easier it will be to plan for defueling the plants. What seems clear now is that, in all likelihood, no sort of indirect testing such as cable continuity is likely to reveal anything about the actual vessel conditions. TEPCO will have to find some other way.

7:15 PM Eastern Wednesday October 19, 2011
ATOMIC POWER REVIEW
Email ThisBlogThis!Share to XShare to FacebookShare to Pinterest
Posted in "fukushima daiichi", "TEPCO" | No comments
Newer Post Older Post Home

0 comments:

Post a Comment

Subscribe to: Post Comments (Atom)

Popular Posts

  • Nitrogen inerting drywells..
    Apparently the nitrogen injection to the drywell on No. 1 plant continues... and TEPCO has made a fairly revealing press release which inclu...
  • NuSource LLC - Press Release
    Press release on formation of NuSource LLC follows. MPR & Gavial Form Joint Venture, NuSource LLC, to Address Nuclear Industry Obsolesce...
  • Nuclear Icebreakers 101
    An addendum for National Nuclear Science Week - Day 3 In the previous post I gave the briefest overview of the history of the Russian fleet ...
  • Atomic History: Dresden-1
    In one of our previous discussions concerning the nature of reactor plant containment, we made considerable effort to detail the very early ...
  • San Onofre seismic study - Press release 4/27
    Press release below from SoCal Ed. Some very interesting news about a cooperative project to further investigate the seismic environment at...
  • Davis-Besse vessel head replacement
    As reported on the NRC blog, Davis-Besse has been shut down for replacement of its pressure vessel head. This plant is a Babcock & Wilco...
  • Carnival 81 on line now
    Dan Yurman has posted the 81st Carnival of Nuclear Bloggers over at his fine blog, "Idaho Samizdat." APR's post on the Decembe...
  • An interesting week, to say the least.
    This has indeed been an interesting week for those who follow the news in nuclear energy. Here is a brief recap from my perspective. NRC CH...
  • Brief Fukushima Daiichi update- Sunday 5/22
    As reported on this blog on April 23, TEPCO has (again) noted the discovery of radioactive debris on the Fukushima Daiichi site which is emi...
  • APR note: APR now on Twitter!
    After much consideration, I have decided to open a Twitter account for Atomic Power Review in order to post relevant news and site updates. ...

Categories

  • " fukushima daiichi"
  • "accident"
  • "alloy"
  • "ameren"
  • "american nuclear society"
  • "annealing"
  • "anniversary"
  • "ans"
  • "anti-nuclear"
  • "AP1000"
  • "arco"
  • "areva"
  • "asn"
  • "associated press" "NRC" "NEI"
  • "atomic journal"
  • "babcock"
  • "blackout"
  • "bloggers"
  • "boron"
  • "brazil"
  • "breeder reactor"
  • "breeder"
  • "browns ferry"
  • "browns ferry" "nine mile point"
  • "BWR"
  • "calhoun"
  • "callaway"
  • "carnival"
  • "chernobyl"
  • "china"
  • "chubu electric" "hamaoka"
  • "chubu" "hamaoka"
  • "chubu" "hamaoka" "tepco" "fukushima daiichi"
  • "chubu" "kyushu" "nisa"
  • "COL"
  • "commissioners"
  • "containment"
  • "contaminated"
  • "cooling"
  • "cooper" "ft calhoun" "flood" "missouri river"
  • "core damage"
  • "criticality"
  • "davis-besse"
  • "delta IV"
  • "dresden" "boiling water reactor" "containment"
  • "dry dock"
  • "dry well"
  • "earth day"
  • "earthquake"
  • "EBR"
  • "ebwr"
  • "education"
  • "elk river"
  • "embrittlement"
  • "enclosure"
  • "energy policy"
  • "equipment"
  • "fabrication"
  • "fermi"
  • "fire"
  • "flood"
  • "frontline"
  • "ft calhoun"
  • "ft calhoun" "oppd" "flood"
  • "ft st vrain"
  • "fukushima daiichi"
  • "fukushima daiichi" "BWR"
  • "fukushima daiichi" "nisa" "tepco"
  • "fukushima daiichi" "tepco"
  • "fukushima daiichi" "tepco" "dry well" "containment" "pressure vessel"
  • "fukushima daiichi" "tepco" "iaea"
  • "fukushima daiichi" "tepco" "kurion" "areva"
  • "fukushima daiichi" "tepco" "nisa"
  • "fukushima daiichi" "tepco" "nisa" "genkai" "pressure vessel"
  • "fukushima daiichi" "tepco" "nisa" "jaif"
  • "fukushima daiichi" "tepco" "nisa" "japan"
  • "fukushima daiichi" "tepco" "nisa" "jsc" "road map" "recovery"
  • "fukushima daiichi" "tepco" "nisa" "spent fuel" "pool"
  • "fukushima daiichi" "tepco" "nitrogen"
  • "fukushima daiichi" "tepco" "robot" "video"
  • "fukushima daiichi" "tepco" "tokai" "japco" "iaea"
  • "fukushima daiichi" "tepco" "tomari" "hokkaido"
  • "fukushima daiichi" "tepco" "tsunami"
  • "fukushima daiichi" "tepco" "video"
  • "fukushima daiichi" "tepco" "video" "youtube"
  • "fukushima daiichi" "TMI" "public opinion" "survey"
  • "fukushima daiichi" "video"
  • "fukushima daiichi" 7 8 plants economic plan TEPCO
  • "fukushima daiichi" cooling water release sea ocean nuclear reactor accident NISA TEPCO pit trench tunnel
  • "fukushima daiichi" nuclear reactor accident contaminated water barge Suzuran Rosatom TEPCO
  • "fukushima daiichi" nuclear reactor accident contaminated water sea radwaste condensers nitrogen hydrogen inert
  • "fukushima daiichi" nuclear reactor accident earthquake onagawa TEPCO tohoku BWR nitrogen
  • "fukushima daiichi" nuclear reactor accident IAEA TEPCO update briefing temperatures pressures
  • "fukushima daiichi" nuclear reactor accident japan update color dye containment fabric update
  • "fukushima daiichi" nuclear reactor accident leakage sea seawater contamination tunnel trench cable pit
  • "fukushima daiichi" nuclear reactor accident liquid glass sodium silicate TEPCO
  • "fukushima daiichi" nuclear reactor accident nitrogen hydrogen inert dry well drywell
  • "fukushima daiichi" nuclear reactor accident nitrogen inert radiolytic radiolysis hydrogen
  • "fukushima daiichi" nuclear reactor accident polymer leak concrete contaminated contamination reactor pressure vessel containment cooling
  • "fukushima daiichi" nuclear reactor accident seawater contamination iodine tunnel trench TEPCO NISA JAIF
  • "fukushima daiichi" nuclear reactor accident site update status project future
  • "fukushima daiichi" nuclear reactor accident sodium silicate liquid glass diagram drawing perspective pipe tunnel trench contamination sea seawater
  • "fukushima daiichi" nuclear reactor accident TEPCO NISA JAIF update
  • "fukushima daiichi" nuclear reactor accident update TEPCO JAIF NISA
  • "fukushima daiichi" nuclear reactor accident water leakage contamination workers found dead
  • "fukushima"
  • "gas cooled"
  • "genkai"
  • "genkai" "embrittlement" "brittle" "pressure vessel"
  • "genkai" "kyushu"
  • "hack job"
  • "hallam"
  • "head"
  • "hearing"
  • "hearings"
  • "higashidori"
  • "hitachi"
  • "HNPF"
  • "hurricane"
  • "hydrogen"
  • "IAEA"
  • "icebreaker"
  • "IFR"
  • "INES"
  • "injection"
  • "irene"
  • "irrelevant"
  • "jaczko"
  • "jaczko" "NRC"
  • "JAIF"
  • "japan"
  • "kurion"
  • "kyushu"
  • "laguna verde"
  • "lenin"
  • "licensing"
  • "loop"
  • "lunch"
  • "marcoule"
  • "mark I"
  • "melt"
  • "meltdown"
  • "mexico"
  • "mitsubishi"
  • "MK I" "containment" "suppression" "youtube" "video"
  • "mPower"
  • "mPower" "Bechtel" "TVA" "babcock"
  • "national nuclear science week"
  • "nei"
  • "new nuclear"
  • "NISA"
  • "nitrogen"
  • "no 5"
  • "no 6"
  • "north anna"
  • "NRC"
  • "NRTS"
  • "nuclear aftershocks"
  • "nuclear energy institute"
  • "nuclear history"
  • "nuclear icebreaker"
  • "office for nuclear regulation"
  • "op-ed"
  • "op-ed" "carnival"
  • "op-ed" "fukushima daiichi"
  • "opinion"
  • "oversight"
  • "palisades"
  • "pbs"
  • "peer review"
  • "poll"
  • "PRA"
  • "press"
  • "pressure vessel"
  • "pressurized thermal shock"
  • "primary to secondary leak"
  • "PTS"
  • "public attitudes"
  • "PWR"
  • "RBMK-1000"
  • "RBMK-1500"
  • "RBMK-2400"
  • "RBMK"
  • "reactor safety"
  • "reading list"
  • "recriticality"
  • "Reid"
  • "reporting"
  • "restart"
  • "risk"
  • "robot"
  • "rod adams" "glenn williams" "interview" "atomic show" "the street"
  • "safety"
  • "san onofre"
  • "sarry"
  • "SBO"
  • "sheldon station"
  • "shippingport"
  • "SMR"
  • "solar"
  • "songs"
  • "south africa"
  • "south texas project"
  • "spent fuel"
  • "SSBN"
  • "steam generator"
  • "steam generators"
  • "steel"
  • "stress tests"
  • "submarine"
  • "support"
  • "Svinicki"
  • "sylcor"
  • "sylvania-corning"
  • "TEPCO"
  • "tepco" "tohoku" "kyushu" "japan"
  • "TMI"
  • "tokyo electric"
  • "Toshiba"
  • "twitter"
  • "UK"
  • "update"
  • "vermont yankee"
  • "vessel"
  • "video"
  • "virgil c summer"
  • "virginia"
  • "vogtle"
  • "wash-1250"
  • "WASH"
  • "westinghouse"
  • "westinghouse" "AP1000" "NRC"
  • "xenon"
  • "youtube"
  • ANO
  • ANS
  • arkansas nuclear one
  • Babcock
  • brittle fracture
  • brookhaven
  • carnival
  • crystal river
  • decommissioning
  • earthquake
  • enriched uranium
  • Entergy
  • fintan dunne
  • FirstEnergy
  • fresno
  • fuel elements
  • fukushima daiichi
  • higashidori
  • hurricane
  • hurricanes
  • industrial accident
  • INES
  • kashiwazaki kariwa TEPCO earthquake
  • kenya
  • license amendment
  • MHI
  • mitsubishi
  • mPower
  • NEI
  • northern fleet
  • nrc
  • nuclear electricity project
  • nuclear history
  • nuclear submarines
  • onagawa tohoku leak earthquake
  • OSHA
  • oyster creek
  • palisades
  • press release
  • pressurized thermal shock
  • PTS
  • retire
  • russian navy
  • san onofre
  • sandy
  • sce
  • sherrell r greene
  • shutdown
  • SMR
  • socal ed
  • songs
  • southern california edison
  • spent fuel
  • spent fuel pool
  • spent fuel pools
  • status
  • steam generator
  • steam generators
  • surry
  • sustainable energy today
  • sylcor
  • sylvania-corning
  • TEPCO
  • tohoku electric power higashidori onagawa LOOP fuel pool cooling
  • tokyo electric power company
  • unusual event

Blog Archive

  • ►  2013 (71)
    • ►  October (5)
    • ►  September (5)
    • ►  August (9)
    • ►  July (5)
    • ►  June (6)
    • ►  May (2)
    • ►  April (8)
    • ►  March (13)
    • ►  February (13)
    • ►  January (5)
  • ►  2012 (159)
    • ►  December (6)
    • ►  November (7)
    • ►  October (13)
    • ►  September (7)
    • ►  August (19)
    • ►  July (15)
    • ►  June (16)
    • ►  May (17)
    • ►  April (13)
    • ►  March (14)
    • ►  February (14)
    • ►  January (18)
  • ▼  2011 (270)
    • ►  December (22)
    • ►  November (21)
    • ▼  October (20)
      • Carnival No. 76 up now...
      • Fukushima Daiichi update: October 28, 2011
      • Report from Fukushima Daiichi - #2
      • New video at APR YouTube
      • Carnival of Nuclear Bloggers No. 75
      • Further test on pressure vessels at Fukushima Daii...
      • Fukushima Daiichi - Emergency Seawater Injection P...
      • Carnival of Nuclear Bloggers up at ANS
      • Davis-Besse containment update
      • Fukushima Daiichi No. 1 enclosed
      • Davis-Besse: Crack in containment building
      • US Energy Policy and the NRC
      • Well done article on Spent Fuel Storage
      • Some new websites.
      • New video: Fukushima Daiichi cooling water injection
      • 73rd Carnival @ Next Big Future
      • New "Favorite" videos at APR Youtube.
      • Davis-Besse vessel head replacement
      • TEPCO: No hydrogen explosion at No. 2 plant
      • ANS Nuclear Cafe / Rod Adams
    • ►  September (21)
    • ►  August (17)
    • ►  July (23)
    • ►  June (24)
    • ►  May (44)
    • ►  April (78)
Powered by Blogger.

About Me

Unknown
View my complete profile