ML19115A235
| ML19115A235 | |
| Person / Time | |
|---|---|
| Site: | 07103052 |
| Issue date: | 02/07/2019 |
| From: | US Dept of Transportation, Pipeline & Hazardous Materials Safety Admin, US Dept of Transportation, Radioactive Materials Branch |
| To: | Office of Nuclear Material Safety and Safeguards |
| References | |
| E-53126 | |
| Download: ML19115A235 (4) | |
Text
Enclosure 1 to E-53126 NRC Questions and Responses
to E-53126 NRC Question and Responses The following issue and comments were from the email dated November 2, 2018, from the NRC to the DOT (Reference 1 in Letter E-53126).
Issue with Calculation and Properties for the Material Strength for Fuel Plates To summarize the issue, we need to resolve:
The Mechanical Criterion in Table 9.2.1 of the French Certificate requires that the yield strength of the aluminum cladding (for the specific fuel being shipped) not be exceeded in an accident.
The most recent changes to the SAR added Appendix 1A-12 to develop the Mechanical Criterion equation.
Table 1A-12.1 provides the aluminum yield strengths that are to be checked-against in order to pass the Mechanical Criterion.
For some alloys in the table (3003, 5052), the aluminum strengths are conservative (low) -
they assume the aluminum to be in an annealed condition (e.g., Temper O).
However, for other alloys (2024, 2014), the aluminum strengths are on the high end of potential strength - they assume a high-strength temper (e.g., Temper T6).
The differences in strength for different tempers can be quite significant. For example, 2014-T6 has a room temperature yield of about 414 MPa (The value in the SAR). However, 2014-O has a yield of only about 100 MPa.
NRC Comment:
As a result, it is not clear that the values in Table 1A-12.1 are reasonably conservative for the alloys that are assumed to have high-strength tempers, absent some technical basis for choosing those tempers.
It is noted that the fuel manufacturer may have procured aluminum to a specific temper; however, the fuel manufacturing process (heating, rolling) and subsequent reactor operation would seem to potentially affect the strength of the material initially received from the aluminum supplier.
NRC Comment/Proposed Solutions:
Some potential solutions may include:
Applicant verification that, when plugging the fuel dimensions into the Mechanical Criterion 1.
equation, the margin is so great that it does not matter which temper is assumed.
Applicant verification that, for the fuel in the subject shipment, the aluminum grades are 2.
those for which low-strength annealed values are provided in Table 1A-12.1 (e.g., 3003, 5052, 5754, 5086, 5083).
Page 1 of 3
to E-53126 NRC Question and Responses That the applicant provide some justification for using data that represent a higher-strength 3.
temper.
This likely warrants a call with TN, if they were to choose the third option. The other two options would not require a call, but one would be requested for assurance. TN is prepared to fulfill whatever condition is imposed.
TNI Response:
Option 2, The applicant verifies that, for the fuel in the subject shipment, the aluminum grades are those for which low-strength annealed values are provided in Table 1A-12.1 (e.g., 3003, 5052, 5754, 5086, 5083), is acceptable to TNI.
The following questions were from the email dated October 31, 2018, from the NRC to DOT (Reference 2 in letter E-53126):
Chapter 3A page 24/32 refers to the Curren and Bond PATRAM paper and the Los Alamos 1.
report when stating a 1E-3 g/m3 concentration of material in aerosols for normal conditions of transport. It would be appreciated if you could provide the page numbers (if possible, the image of those pages) in each of those two references that indicate the 1E-3 g/m3 value is relevant in the revalidation containment release calculations TNI Response:
A guide to radiological accident considerations for siting and design of DOE non-reactor nuclear facilities. - LA 10294-MS - UC 41 - January 1986 - Los Alamos National Laboratory, New Mexico, USA.
https://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-10294-MS It is on page 28 in the table VIII. The specific area where the aerosols values are is identified.
Patram 80 paper:
https://digital.library.unt.edu/ark:/67531/metadc1100599/m1/486/zoom/?resolution=2&lat=35 46.3637584062744&lon=810.0000000000001.
The article is from pages 486 to 494 (see page 493).
The specific paper has been extracted from the link and specific area where the aerosols values are discussed is identified and is on document page 470 (PDF page 11).
A copy of each document is included as Enclosures 2 and 3, respectively.
Provide Reference 8: TN International Note ref. NTC-07-0085519-000 Synthse des essais 2.
de détermination du coefficient de perméabilité sur élastomre FKM et EPDM (Summary of tests used to determine the permeability coefficient on FKM and EPDM elastomer seals). Provide an English translation?
Page 2 of 3
to E-53126 NRC Question and Responses TNI Response:
The English translation is included as Enclosure 4. This enclosure is proprietary.
Provide Reference 10: Gas permeation through common elastomer sealing material - H.-P 3.
Weise, K. -H Ecker, H. Kowalewsky, Th. Wolk bundesantalt fur Material forschung and prufung (BAM), Berlin F.R.G. - Vuoto -1990. Provide an English translation?
TNI Response TN contacted BAM regarding this specific publication. Unfortunately, our contact at BAM was unable to locate the original publication. However, our contact at BAM did locate a copy of a PATRAM 86 (June 1986) publication by the same title. This publication deals with the same topic. A copy of the document is included as Enclosure 5.
In addition, it is requested that TN explain what is meant by the references <13><3> and 4.
<14><4> in the first sentence found in section 7.1 and section 7.2 (page 24/32 of Chapter 3A). It is noted that there are only 11 references (no reference 13 or 14) listed on page 30/32.
TNI Response:
This is a translation error: References <13> and <14> do not exist.
Page 3 of 3