Fukushima robot stranded after stalling inside reactor

[jakeXT]

Source: Guardian

Decommissioning work at the Fukushima Daiichi nuclear power plant has suffered a setback after a robot sent in to a damaged reactor to locate melted fuel stalled hours into its mission and had to be abandoned.

The plant’s operator, Tokyo Electric Power (Tepco), said the robot stopped moving on Friday during its first inspection of the containment vessel inside reactor No 1, one of the three reactors that suffered meltdown after the plant was struck by an earthquake and tsunami in March 2011.

Tepco, which recently conceded that the technology for robots to retrieve the nuclear fuel had yet to be developed, said on Monday it would cut the cables to the stranded robot and postpone a similar inspection using a separate device.

Developed by Hitachi-GE Nuclear Energy and the International Research Institute for Nuclear Decommissioning, the robot was supposed to be able to function for about 10 hours even when exposed to radiation at levels that would cause ordinary electronic devices to malfunction.



Read more: http://www.theguardian.com/environment/2015/apr/13/fukushima-robot-stalls-reactor-abandoned

[Plucketeer]

1. We're only good at F-ing up the earth

not at making it right again.

[Trillo]

2. Back to the robot-engineering board.

It was designed for 10 hours, but only worked for 3.

[daleo]

17. One possible explanation

Radiation levels are 3.3 times higher than they expected.

[FBaggins]

22. They were actually lower

But why spoil a good story, right?

[Octafish]

34. 10 Sv/hour was the reading reported by the Japan Times.

''a level fatal for humans."

http://www.japantimes.co.jp/news/2015/04/15/national/tepco-resumes-survey-crippled-fukushima-reactor-vessel-new-robot/#.VS5LsPnF-UU

Where did you get your

[FBaggins]

35. And that was lower than expected

According to Tepco spokesman Teruaki Kobayashi radiation was significantly lower than expected, so that future robots could remain in the reactor longer and wireless data connections are conceivable

http://khon2.com/2015/04/14/tepco-abandons-robot-stranded-inside-fukushima-plant-some-data-received/

a level fatal for humans

A classic "duh" moment.

What did you expect? We're not talking about tiny amounts of volatile isotopes that can barely be picked out of the background radiation levels. We're talking about physical pieces of nuclear fuel. Of course the dose rate is going to be much higher.

Just not as high as they expected.

My speculation is that they assumed that the melt-through occurred early (and quickly) enough that the molten corium "sprayed" out of the bottom of the RPV rather than flowing as a relatively cohesive mass. That would leave much of the corium all over this level and potential dose rate would be a couple orders of magnitude higher.

Don't worry...you'll see some very high readings once they send a waterproof unit to the lower level.

FYI -The second robot entered containment yesterday.

[Octafish]

36. 'A classic "duh" moment.'

Says it all about you, FBaggins.

[Calista241]

26. I find it unbelievable that we can send a robot

To Mars and can't get a robot to investigate this.

Think what Curiosity had to go through to get to Mars, and is performing more or less perfectly.

[FBaggins]

28. It wasn't "designed for ten hours"

The mission was expected to take that long. They were actually able to complete ~2/3 of the mission (including the primary goal) before the unit got stuck.

[KamaAina]

3. This would make one hell of a sci-fi movie!

[bananas]

4. Or a reality-TV show! nt

[The Stranger]

5. Was it fried by the radiation in there?

[jakeXT]

6. 9.7 sievert, enough to kill humans... I don't know about robots

Radiation measured at deadly 9.7 sieverts in Fukushima reactor

Tokyo Electric Power Co. said Monday that radiation in the primary containment vessel of the No. 1 reactor of the Fukushima No. 1 power station gets as high as 9.7 sieverts per hour — enough to kill a human within an hour.

http://www.japantimes.co.jp/news/2015/04/13/national/radiation-measured-at-deadly-9-7-sieverts-in-fukushima-reactor/

[AtheistCrusader]

9. Ionizing radiation is bad for electronics. You can shield them, but at some point the shielding

weighs so much it stops being a robot, and starts being an appliance that doesn't go anywhere. The radiation near the containment is high enough to disrupt electronics, so this is to be expected, unfortunately.

[bemildred]

21. Which is one reason putting computers in everything, while good for Intel, is stupid.

In exchange for being cheap, mechanical systems give you reliability, maintainability, and tolerance of normal environmental hazards. I love old mechanical stuff because it works forever and you can fix it. You do not spend your days learnng the latest stuff that some nerd in Redmond came up with.

[benld74]

7. Wall-e never got a fair break either

[chervilant]

8. hmm...

Developed by Hitachi-GE Nuclear Energy and the International Research Institute for Nuclear Decommissioning, the robot was supposed to be able to function for about 10 hours even when exposed to radiation at levels that would cause ordinary ELECTRONIC devices to malfunction.

Let's see...

--"it's only as much radiation as you would get eating a few bananas."

--"it's the equivalent of having two __________." (fill in the blank with your favorite fruit or vegetable.)

--"it's less radiation than you'd get from an x-ray."

--"the Pacific is HUGE, and will disperse the radiation until it's no longer harmful."

How many more of these statements have you read, right here on DU?

Fukushima is and will be a major catastrophe, for decades to come. The NIMBY folks seem to be struggling hard to deny that fact.

[AtheistCrusader]

10. Dosage, it's a thing. Who knew?

Ridiculous out of context quotes aside.

[questionseverything]

12. i wonder if this pacific warming is not related too

http://www.democraticunderground.com/112783963

i am no scientist but i know the cooling pond for our local nuke plant's water is warm year round

unfortunately at this point it doesn't look like we will have to wait for global warming to kill the oceans ,looks like we are already there

[AtheistCrusader]

14. Fully unrelated.

There have been a couple 'fukushima is heating the pacific' threads, but no, physically impossible. Whatever is left of the cores at that site, they are only putting out decay heat, which is a teeny tiny fraction of the thermal output of a working reactor core. 'Hot' in more than one sense, but not mW of thermal output.

http://www.democraticunderground.com/10022750608

[RobertEarl]

18. Nuke plants are made to heat water

Nuclear spent fuel, when contained {but it so happens much Fukushima material is in the Pacific, see the cesium found at Vancouver?} create heat for years and years.

Not only that, but when the earthquake tore up the piping and the 3 active cores puked their guts, that puke went right into the ocean. Hot stuff, man. Hot stuff.

[FBaggins]

23. Then why isn't the pacific cooler?

Last edited Tue Apr 14, 2015, 07:46 AM - Edit history (1)

Japan has after all turned dozens of units off for over two years now.

You really think that each of those melted cores is producing 20+ times as much heat as when it was actually active?

Can't wait to hear the "science" on this one.

[jakeXT]

31. The only reactor that could do it is probably in the center

[RobertEarl]

37. The possibility is there

No one is saying the sole reason for the extra heating is due to Fukushima, but science does make a case for the heat from melted cores and the alkali chemicals to be a contributing factor in the anomaly. To deny that is to be a science denier.

[Myrina]

11. You go get it! Nuh-uh, you! No way, man, YOU do it!!

[bemildred]

13. Nasty stuff, radiation. nt

[DeSwiss]

15. K&R

- There is this famous Greek saying: ''?? ?ά?? ????ά?? ??ό ?? ???ά??.'' (The fish stinks from the head.) Which in today's terms would translate into: ''Your Prime Minister is driving your country into a shithole from which it will never reemerge.''

[mrdmk]

19. Japan is a blasting of liberal politics it just blows the mind

Really, no wonder they cannot get this Fukushima problem fixed.

[Monk06]

16. Time to put Carlos Ghosn in charge

[Ichingcarpenter]

20. This robot was three years in its making

three years ago Toshiba launches radiation-proof robot to clean up Fukushima The robot, which was specially designed to help decommission Japan's crippled Fukushima Daichi nuclear plant, features a dosimeter to measure radiation and six cameras.


http://rt.com/news/fukushima-radiation-proof-robot-292/

I see a runaway major world catastrophic fuck us that they an't telling the world............... three years for that robot... they don't know if they will launch another and they really don't know how to fix this.

[dembotoz]

24. that is the thing about technology-sometimes the damn thing just does not work

lets hope they figure out what went wrong with plan a and come up with a better plan b

[Ichingcarpenter]

25. lets hope but that company is the number one for robot tech in the world

and it took three years to send it into the pit of hell


Remember when they had the giant ice dam plan for the reactors?
what happened to that?

Listen, my dad worked in the science of nukes so I know things that Tepco and the Japanese govt is not telling the public because of the implications of facing that reality.

anyway has my sig says..............DON'T PANIC........

[FBaggins]

27. There isn't any evidence that there's anything wrong with the robot

Certainly nothing related to radiation exposure.

It looks like they drove it into a spot that they can't get it out of. That's user error, not system failure.

[Ichingcarpenter]

29. Well wait three more years until they get the next robot built

still doesn't mean shit....... they don't know how to fix it and they admitted it.

[FBaggins]

30. You're kidding, right?

They have mutliple units built. A second one was scheduled to go in yesterday from the other side of the containment, but that was delayed while they investigate how this one got stuck.

Then there's a follow-on model that's waterproof so that it can go further down to examine the corium. That's due to be completed around the end of the year.