ScribbleLive

www2.jnes.go.jp
July 2000 JNES- INES report on Daiichi #6

2. Cause and Countermeasures

As a result of the investigation, a crack was recognized in the fitting screw portion of the crossaround pipe relief valve tailpipe. The crossaround pipe is a steam pipe which connects the high pressure turbine with the low pressure turbine. As a result of investigating the concerned fitting screw portion, the cause is estimated as follows: Stress was repeatedly added to the fitting screw root portion due to transformation of the crossaround pipe with thermal expansion and contraction due to plant startup and shutdown　operations. The crack generated and developed, and resulted in a wall-through of the screw for almost whole circumference. The tailpipe is estimated to have finally opened due to the earthquake force.
www2.jnes.go.jp
11yrs later and they say the quake in March caused no damage hmph

back.. awwwwww.. nice break

elaine. that flower always makes the day...

nice links elaine

I will go study these elaine and eat alittle before I ride..

will do elaine

@dean I have no idea I just thought they would be a good research tool

@Nancy that is erm...interesting

I will check and be back

Press Release (Apr 30,2011)
Instruction to submit report regarding the implementation of a measure to flood primary containment vessel to the upper area of fuel range in Unit 1 of Fukushima Daiichi Nuclear Power Station


Today we have received instruction from Nuclear and Industrial Safety
Agency (NISA) to submit report based on article 67, clause 1 of Act on the
Regulation of Nuclear Source Material, Nuclear Fuel Material and Reactors
(law number 166, 1957).

We will evaluate the effect to stable reactor cooling and safety of a
measure to flood primary containment vessel to the upper area of fuel
range in Unit 1 of Fukushima Daiichi Nuclear Power Station and report to
NISA.

*Instruction Notice
Submission of report regarding the implementation of a measure to flood
primary containment vessel to the upper area of fuel range in Unit 1 of
Fukushima Daiichi Nuclear Power Station

NISA no.1, 2011.4.30
April 30, 2011

NISA hereby instructs TEPCO to report the following matters in timely
manner based on article 67, clause 1 of Act on the Regulation of Nuclear
Source Material, Nuclear Fuel Material and Reactors in order to evaluate
the appropriateness of an emergency measure planned by TEPCO.

In case TEPCO disagrees with this instruction, it is entitled to make a
formal objection in writing to the minister of economy, trade, and
industry based on Administrative Appeal Act (law number 160, 1962) within
60 days from the next day when it recognizes the instruction. However, it
is not entitled to do so after one year from the next day of the
instruction even if within 60 days from the next day when it recognizes
the instruction.

After the treatment of a formal objection is determined, action for
rescission of a disposition can be made against the government
(representative: ministry of law) based on Administrative Case Litigation
Act (law number 139, 1962) within 6 month from the next day when it
recognizes the determination of treatment of a formal objection. However,
it is not entitled to do so after one year from the next day of the
determination even if within 6 months from the next day when it recognizes
the determination.

In case of the followings, TEPCO is entitled to make action for rescission
of a disposition without the determination of treatment of a formal
objection. 1: treatment is not determined within 3 month from the next day
when a formal objection is made. 2. there is urgent need to avoid
significant damage caused by disposal, execution of disposal and
continuation of execution. 3. there is a justifiable ground for not having
determination of treatment.

Submission of report regarding the effect to stable reactor cooling and
safety of a measure to flood primary containment vessel to the upper area
of fuel range in Unit 1 of Fukushima Daiichi Nuclear Power Station.

1.impact on structural strength and earthquake resistance of reactor
building and primary containment vessel from the water level increase in
primary containment vessel
* Result of impact analysis on the structural strength of structure and
facilities in primary containment vessel including reactor building, dry
well, and suppression chamber from the water level increase in primary
containment vessel
* Result of evaluation whether reactor building and structure and
facilities in primary containment vessel can sustain the designed
seismic force.
2.impact from the pressure increase inside primary containment vessel.
* Estimation of the pressure increase inside primary containment vessel
from the water level increase
* Result of the analysis on the necessity of countermeasure to reduce
the pressure inside primary containment vessel considering the above
estimation.
3.impact from the increase of leaking water in turbine building
* Estimation of amount of leaking water at present and in the future and
possibility of leakage to outside environment.
4.Other issues relating to safety evaluation regarding the implementation
of a measure to flood primary containment vessel to the upper area of
fuel range. www.tepco.co.jp