ML20128N300
| ML20128N300 | |
| Person / Time | |
|---|---|
| Site: | 07106639 |
| Issue date: | 05/22/1985 |
| From: | Odegaarden R NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| To: | NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| NUDOCS 8506030228 | |
| Download: ML20128N300 (3) | |
Text
r 7 -(o63 7 Distribution: w/ encl Mtg attendees GBeveridge Docket File FCTC Mtg Book NMSS R/F FCTC: RHO MY22 W FCTC R/F 71-6639 # D&
RETWtli TO A. Nacidia R SS 14 Eft 0RAf!DUti FOR: 'The Files
.FROM: Richard H. Odegaarden, FCTC, filtSS
SUBJECT:
SUtiMARY OF ltEETING WITH DOE CONCERNING MODEL NO. PJi-1A APPLICATION DATED FEBRUARY 19, 1985 Attendees 00E 00T BNL Sandia NRC D. Leclaire L. Santman J. t!ceks W. Wowak R. Cunninghan C. Caves R. Rawl P. Tichler C. MacDonald R. Garrison E. Economides R. Odegaarden C. Mauck C. Chappell K. Elliott 11. Lee
- 11. Crawford J. Cook (consultant)
Introeuction i
A neeting was held at Silver Spring, Maryland, on itay 21,1985, at the '
request of the Nuclear Regulatory Comnission (NRC) to discuss preliminary findings of the NRC staff's structural review of the application for the Podel No. Mil-1A package.
Discussion The enclosed comnents on the structural analysis were discussed. 00E -
indicated that they would further assess our comments and take appropriate action in the interim.
Original Signed by caAms3 g, MACDONALD e50603022s850g39
. PDR ADOCK 071 PDR Richard 11. Odegaarden .
C Transportation Certification Branch Division of Fuel Cycle and f!aterial, Safety,tctSS
Enclosure:
As stated
~~m* C
[CTC , FCTCys ,
'=J-4t0deg rden: alm CEMacDonald R ,
ingham ,
l im*
05/2Y/,85 05/ W 85 / 85 - -
NMC FORM M8 00 80) NRCM ONO OFFICIAL RECORD COPY
I Agenda Meeting on Application for NRC Certification __
Model No. MH-1A Package Docket No. 71-6639 May 21, 1985 The Problem The premise upon which the application is based is that the package will retain all contents, including radioactive gases, following the accident condition tests in 10 CFR 71. Although this approach might not be the only way in which the package could be demonstrated to meet 10 CFR 71, the analysis in the application is intended to demonstrate that the package will remain leak-tight. The staff's preliminary finding is that the structural pcrtion of the analysis contained in the application is defective and does not provide a basis to support the conclu-sions drawn in the application. Attached is a summary which identifies, in abbreviated form, our principal comments on the structural analysis.
The staff is aware that the Model No. MH-1A package is presently being used to ship DOE irradiated fuel under a DOE certification. The staff believes it is likely that the analytical basis of the DOE certification is similar to, if not the same as, the one contained in Docket No. 71-6639. Accordingly, the staff also believes it is obliged to draw to the attention of appropriate DOE and D0T officials -
its present conclusions about the structural analysis.
Purpose of Meeting The staff is aware that our comments on the structural analysis could have a disruptive effect on the present DOE shipping campaign. Therefore, the purpose of this meeting is to review the issues with the engineers responsible for the structural analysis in the application to determine if there is additional infor-mation or clarifications which would cause the staff to change its present conclusions.
3-Summary of Deficiencies in the Structural Evaluation
- 1. The application specifies criteria for allowable stresses but many of the _m calculated stresses exceed those criteria.
~
- 2. The. application does not analyze the cask for various normal and accident conditions which could produce governing stress (e.g., 2-foot free drop, 30-foot oblique impact condition).
- 3. The application does not consider the combined effect of all the loads which act simultaneously on the containment vessel (e.g., impact and hot or cold ambient temperatures).
- 4. The buckling evaluation in the application is not adequate to show that the containment vessel would not buckle under 30-foot drop test conditions.
The evaluation does not consider possible inelastic buckling even though stresses in the shell were calculated to be above yield. The application also does not consider the combined effect of all the loads which act simultaneously.
- 5. The application does not report the stresses in the closure bolts or in the drain / vent lines which pass through the lead shielding.
- 6. The application does not analyze the stresses in the bottom end plate of the cask or in the bottom plate of the containment vessel. ~
- 7. The application does not consider potential displacement of shielding due to " lead slump."
- 8. The puncture evaluation does not consider potential collapse of the top closure plate or the bottom end plate.
- 9. The analysis of structural interaction between the lead shielding and the containment vessel does not consider the lateral pressure exerted by the lead against the containment vessel under 30-foot drop or differential thermal expansion and contraction.
- 10. The finite element analysis and the stress calculations do not provide sufficient information for review. The assumptions and inputs such as element properties, loads, and loading distributions were not described in detail and justified.
- 11. Static properties were used to analyze the redwood impact limiters for drop orientations where the redwood is crushed perpendicular to the grain. Infor-mation in a Sandia Laboratories report indicates the dynamic properties could be substantially different. Selection of the static properties for the analysis should be justified.